Merge remote-tracking branch 'origin/master' into datatype-date32

2024-11-10 09:32:06 +00:00 · 2021-07-05 10:15:08 +08:00 · 2021-07-05 10:15:08 +08:00 · dc0c65ef4f
commit dc0c65ef4f
parent b87814205d 9a33dd8f9f
363 changed files with 5274 additions and 2244 deletions
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@ -184,10 +184,27 @@ endif ()
 set (CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -rdynamic")

 find_program (OBJCOPY_PATH NAMES "llvm-objcopy" "llvm-objcopy-12" "llvm-objcopy-11" "llvm-objcopy-10" "llvm-objcopy-9" "llvm-objcopy-8" "objcopy")
+
+if (NOT OBJCOPY_PATH AND OS_DARWIN)
+    find_program (BREW_PATH NAMES "brew")
+    if (BREW_PATH)
+        execute_process (COMMAND ${BREW_PATH} --prefix llvm ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE OUTPUT_VARIABLE LLVM_PREFIX)
+        if (LLVM_PREFIX)
+            find_program (OBJCOPY_PATH NAMES "llvm-objcopy" PATHS "${LLVM_PREFIX}/bin" NO_DEFAULT_PATH)
+        endif ()
+        if (NOT OBJCOPY_PATH)
+            execute_process (COMMAND ${BREW_PATH} --prefix binutils ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE OUTPUT_VARIABLE BINUTILS_PREFIX)
+            if (BINUTILS_PREFIX)
+                find_program (OBJCOPY_PATH NAMES "objcopy" PATHS "${BINUTILS_PREFIX}/bin" NO_DEFAULT_PATH)
+            endif ()
+        endif ()
+    endif ()
+endif ()
+
 if (OBJCOPY_PATH)
-   message(STATUS "Using objcopy: ${OBJCOPY_PATH}.")
+    message (STATUS "Using objcopy: ${OBJCOPY_PATH}")
 else ()
-  message(FATAL_ERROR "Cannot find objcopy.")
+    message (FATAL_ERROR "Cannot find objcopy.")
 endif ()

 if (OS_DARWIN)
--- a/base/common/DateLUT.h
+++ b/base/common/DateLUT.h
@ -17,7 +17,7 @@ class DateLUT : private boost::noncopyable
 {
 public:
    /// Return singleton DateLUTImpl instance for the default time zone.
-    static ALWAYS_INLINE const DateLUTImpl & instance()
+    static ALWAYS_INLINE const DateLUTImpl & instance()  // -V1071
    {
        const auto & date_lut = getInstance();
        return *date_lut.default_impl.load(std::memory_order_acquire);
--- a/cmake/autogenerated_versions.txt
+++ b/cmake/autogenerated_versions.txt
@ -1,9 +1,9 @@
 # This strings autochanged from release_lib.sh:
-SET(VERSION_REVISION 54452)
+SET(VERSION_REVISION 54453)
 SET(VERSION_MAJOR 21)
-SET(VERSION_MINOR 7)
+SET(VERSION_MINOR 8)
 SET(VERSION_PATCH 1)
-SET(VERSION_GITHASH 976ccc2e908ac3bc28f763bfea8134ea0a121b40)
-SET(VERSION_DESCRIBE v21.7.1.1-prestable)
-SET(VERSION_STRING 21.7.1.1)
+SET(VERSION_GITHASH fb895056568e26200629c7d19626e92d2dedc70d)
+SET(VERSION_DESCRIBE v21.8.1.1-prestable)
+SET(VERSION_STRING 21.8.1.1)
 # end of autochange
--- a/cmake/embed_binary.cmake
+++ b/cmake/embed_binary.cmake
@ -33,44 +33,25 @@ macro(clickhouse_embed_binaries)
        message(FATAL_ERROR "The list of binary resources to embed may not be empty")
    endif()

-    # If cross-compiling, ensure we use the toolchain file and target the
-    # actual target architecture
-    if (CMAKE_CROSSCOMPILING)
-        set(CROSS_COMPILE_FLAGS "--target=${CMAKE_C_COMPILER_TARGET} --gcc-toolchain=${TOOLCHAIN_FILE}")
-    else()
-        set(CROSS_COMPILE_FLAGS "")
-    endif()
+    add_library("${EMBED_TARGET}" STATIC)
+    set_target_properties("${EMBED_TARGET}" PROPERTIES LINKER_LANGUAGE C)

    set(EMBED_TEMPLATE_FILE "${PROJECT_SOURCE_DIR}/programs/embed_binary.S.in")
-    set(RESOURCE_OBJS)
-    foreach(RESOURCE_FILE ${EMBED_RESOURCES})
-        set(RESOURCE_OBJ "${RESOURCE_FILE}.o")
-        list(APPEND RESOURCE_OBJS "${RESOURCE_OBJ}")

-        # Normalize the name of the resource
+    foreach(RESOURCE_FILE ${EMBED_RESOURCES})
+        set(ASSEMBLY_FILE_NAME "${RESOURCE_FILE}.S")
        set(BINARY_FILE_NAME "${RESOURCE_FILE}")
+
+        # Normalize the name of the resource.
        string(REGEX REPLACE "[\./-]" "_" SYMBOL_NAME "${RESOURCE_FILE}") # - must be last in regex
        string(REPLACE "+" "_PLUS_" SYMBOL_NAME "${SYMBOL_NAME}")
-        set(ASSEMBLY_FILE_NAME "${RESOURCE_FILE}.S")

-        # Put the configured assembly file in the output directory.
-        # This is so we can clean it up as usual, and we CD to the
-        # source directory before compiling, so that the assembly
-        # `.incbin` directive can find the file.
+        # Generate the configured assembly file in the output directory.
        configure_file("${EMBED_TEMPLATE_FILE}" "${CMAKE_CURRENT_BINARY_DIR}/${ASSEMBLY_FILE_NAME}" @ONLY)

-        # Generate the output object file by compiling the assembly, in the directory of
-        # the sources so that the resource file may also be found
-        add_custom_command(
-            OUTPUT ${RESOURCE_OBJ}
-            COMMAND cd "${EMBED_RESOURCE_DIR}" &&
-                 ${CMAKE_C_COMPILER} "${CROSS_COMPILE_FLAGS}" -c -o
-                    "${CMAKE_CURRENT_BINARY_DIR}/${RESOURCE_OBJ}"
-                    "${CMAKE_CURRENT_BINARY_DIR}/${ASSEMBLY_FILE_NAME}"
-        )
-        set_source_files_properties("${RESOURCE_OBJ}" PROPERTIES EXTERNAL_OBJECT true GENERATED true)
-    endforeach()
+        # Set the include directory for relative paths specified for `.incbin` directive.
+        set_property(SOURCE "${CMAKE_CURRENT_BINARY_DIR}/${ASSEMBLY_FILE_NAME}" APPEND PROPERTY INCLUDE_DIRECTORIES "${EMBED_RESOURCE_DIR}")

-    add_library("${EMBED_TARGET}" STATIC ${RESOURCE_OBJS})
-    set_target_properties("${EMBED_TARGET}" PROPERTIES LINKER_LANGUAGE C)
+        target_sources("${EMBED_TARGET}" PRIVATE "${CMAKE_CURRENT_BINARY_DIR}/${ASSEMBLY_FILE_NAME}")
+    endforeach()
 endmacro()
--- a/cmake/linux/toolchain-aarch64.cmake
+++ b/cmake/linux/toolchain-aarch64.cmake
@ -4,7 +4,6 @@ set (CMAKE_C_COMPILER_TARGET "aarch64-linux-gnu")
 set (CMAKE_CXX_COMPILER_TARGET "aarch64-linux-gnu")
 set (CMAKE_ASM_COMPILER_TARGET "aarch64-linux-gnu")
 set (CMAKE_SYSROOT "${CMAKE_CURRENT_LIST_DIR}/../toolchain/linux-aarch64/aarch64-linux-gnu/libc")
-get_filename_component (TOOLCHAIN_FILE "${CMAKE_TOOLCHAIN_FILE}" REALPATH)

 # We don't use compiler from toolchain because it's gcc-8, and we provide support only for gcc-9.
 set (CMAKE_AR "${CMAKE_CURRENT_LIST_DIR}/../toolchain/linux-aarch64/bin/aarch64-linux-gnu-ar" CACHE FILEPATH "" FORCE)
--- a/contrib/NuRaft
+++ b/contrib/NuRaft
@ -1 +1 @@
-Subproject commit 2a1bf7d87b4a03561fc66fbb49cee8a288983c5d
+Subproject commit 976874b7aa7f422bf4ea595bb7d1166c617b1c26
--- a/contrib/murmurhash/CMakeLists.txt
+++ b/contrib/murmurhash/CMakeLists.txt
@ -1,7 +1,7 @@
 add_library(murmurhash
-    src/murmurhash2.cpp
-    src/murmurhash3.cpp
-    include/murmurhash2.h
-    include/murmurhash3.h)
+    src/MurmurHash2.cpp
+    src/MurmurHash3.cpp
+    include/MurmurHash2.h
+    include/MurmurHash3.h)

 target_include_directories (murmurhash PUBLIC include)
--- a/contrib/murmurhash/include/MurmurHash2.h
+++ b/contrib/murmurhash/include/MurmurHash2.h
@ -0,0 +1,49 @@
+//-----------------------------------------------------------------------------
+// MurmurHash2 was written by Austin Appleby, and is placed in the public
+// domain. The author hereby disclaims copyright to this source code.
+
+#ifndef MURMURHASH2_H
+#define MURMURHASH2_H
+
+#include <stddef.h>
+
+//-----------------------------------------------------------------------------
+// Platform-specific functions and macros
+
+// Microsoft Visual Studio
+
+#if defined(_MSC_VER) && (_MSC_VER < 1600)
+
+typedef unsigned char uint8_t;
+typedef unsigned int uint32_t;
+typedef unsigned __int64 uint64_t;
+
+// Other compilers
+
+#else	// defined(_MSC_VER)
+
+#include <stdint.h>
+
+#endif // !defined(_MSC_VER)
+
+//-----------------------------------------------------------------------------
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+uint32_t MurmurHash2        ( const void * key, size_t len, uint32_t seed );
+uint64_t MurmurHash64A      ( const void * key, size_t len, uint64_t seed );
+uint64_t MurmurHash64B      ( const void * key, size_t len, uint64_t seed );
+uint32_t MurmurHash2A       ( const void * key, size_t len, uint32_t seed );
+uint32_t MurmurHashNeutral2 ( const void * key, size_t len, uint32_t seed );
+uint32_t MurmurHashAligned2 ( const void * key, size_t len, uint32_t seed );
+
+#ifdef __cplusplus
+}
+#endif
+
+//-----------------------------------------------------------------------------
+
+#endif // _MURMURHASH2_H_
+
--- a/contrib/murmurhash/include/MurmurHash3.h
+++ b/contrib/murmurhash/include/MurmurHash3.h
@ -2,7 +2,10 @@
 // MurmurHash3 was written by Austin Appleby, and is placed in the public
 // domain. The author hereby disclaims copyright to this source code.

-#pragma once
+#ifndef MURMURHASH3_H
+#define MURMURHASH3_H
+
+#include <stddef.h>

 //-----------------------------------------------------------------------------
 // Platform-specific functions and macros
@ -23,20 +26,22 @@ typedef unsigned __int64 uint64_t;

 #endif // !defined(_MSC_VER)

+//-----------------------------------------------------------------------------
+
 #ifdef __cplusplus
 extern "C" {
 #endif

-//-----------------------------------------------------------------------------
+void MurmurHash3_x86_32  ( const void * key, size_t len, uint32_t seed, void * out );

-void MurmurHash3_x86_32  ( const void * key, int len, uint32_t seed, void * out );
+void MurmurHash3_x86_128 ( const void * key, size_t len, uint32_t seed, void * out );

-void MurmurHash3_x86_128 ( const void * key, int len, uint32_t seed, void * out );
-
-void MurmurHash3_x64_128 ( const void * key, int len, uint32_t seed, void * out );
-
-//-----------------------------------------------------------------------------
+void MurmurHash3_x64_128 ( const void * key, size_t len, uint32_t seed, void * out );

 #ifdef __cplusplus
 }
 #endif
+
+//-----------------------------------------------------------------------------
+
+#endif // _MURMURHASH3_H_
--- a/contrib/murmurhash/include/murmurhash2.h
+++ b/contrib/murmurhash/include/murmurhash2.h
@ -1,31 +0,0 @@
-//-----------------------------------------------------------------------------
-// MurmurHash2 was written by Austin Appleby, and is placed in the public
-// domain. The author hereby disclaims copyright to this source code.
-
-#pragma once
-
-//-----------------------------------------------------------------------------
-// Platform-specific functions and macros
-
-// Microsoft Visual Studio
-
-#if defined(_MSC_VER) && (_MSC_VER < 1600)
-
-typedef unsigned char uint8_t;
-typedef unsigned int uint32_t;
-typedef unsigned __int64 uint64_t;
-
-// Other compilers
-
-#else	// defined(_MSC_VER)
-
-#include <stdint.h>
-
-#endif // !defined(_MSC_VER)
-
-uint32_t MurmurHash2        (const void * key, int len, uint32_t seed);
-uint64_t MurmurHash64A      (const void * key, int len, uint64_t seed);
-uint64_t MurmurHash64B      (const void * key, int len, uint64_t seed);
-uint32_t MurmurHash2A       (const void * key, int len, uint32_t seed);
-uint32_t MurmurHashNeutral2 (const void * key, int len, uint32_t seed);
-uint32_t MurmurHashAligned2 (const void * key, int len, uint32_t seed);
--- a/contrib/murmurhash/src/MurmurHash2.cpp
+++ b/contrib/murmurhash/src/MurmurHash2.cpp
@ -0,0 +1,523 @@
+//-----------------------------------------------------------------------------
+// MurmurHash2 was written by Austin Appleby, and is placed in the public
+// domain. The author hereby disclaims copyright to this source code.
+
+// Note - This code makes a few assumptions about how your machine behaves -
+
+// 1. We can read a 4-byte value from any address without crashing
+// 2. sizeof(int) == 4
+
+// And it has a few limitations -
+
+// 1. It will not work incrementally.
+// 2. It will not produce the same results on little-endian and big-endian
+//    machines.
+
+#include "MurmurHash2.h"
+
+//-----------------------------------------------------------------------------
+// Platform-specific functions and macros
+
+// Microsoft Visual Studio
+
+#if defined(_MSC_VER)
+
+#define BIG_CONSTANT(x) (x)
+
+// Other compilers
+
+#else	// defined(_MSC_VER)
+
+#define BIG_CONSTANT(x) (x##LLU)
+
+#endif // !defined(_MSC_VER)
+
+//-----------------------------------------------------------------------------
+
+uint32_t MurmurHash2 ( const void * key, size_t len, uint32_t seed )
+{
+  // 'm' and 'r' are mixing constants generated offline.
+  // They're not really 'magic', they just happen to work well.
+
+  const uint32_t m = 0x5bd1e995;
+  const int r = 24;
+
+  // Initialize the hash to a 'random' value
+
+  uint32_t h = seed ^ len;
+
+  // Mix 4 bytes at a time into the hash
+
+  const unsigned char * data = (const unsigned char *)key;
+
+  while(len >= 4)
+  {
+    uint32_t k = *(uint32_t*)data;
+
+    k *= m;
+    k ^= k >> r;
+    k *= m;
+
+    h *= m;
+    h ^= k;
+
+    data += 4;
+    len -= 4;
+  }
+
+  // Handle the last few bytes of the input array
+
+  switch(len)
+  {
+  case 3: h ^= data[2] << 16;
+  case 2: h ^= data[1] << 8;
+  case 1: h ^= data[0];
+      h *= m;
+  };
+
+  // Do a few final mixes of the hash to ensure the last few
+  // bytes are well-incorporated.
+
+  h ^= h >> 13;
+  h *= m;
+  h ^= h >> 15;
+
+  return h;
+} 
+
+//-----------------------------------------------------------------------------
+// MurmurHash2, 64-bit versions, by Austin Appleby
+
+// The same caveats as 32-bit MurmurHash2 apply here - beware of alignment 
+// and endian-ness issues if used across multiple platforms.
+
+// 64-bit hash for 64-bit platforms
+
+uint64_t MurmurHash64A ( const void * key, size_t len, uint64_t seed )
+{
+  const uint64_t m = BIG_CONSTANT(0xc6a4a7935bd1e995);
+  const int r = 47;
+
+  uint64_t h = seed ^ (len * m);
+
+  const uint64_t * data = (const uint64_t *)key;
+  const uint64_t * end = data + (len/8);
+
+  while(data != end)
+  {
+    uint64_t k = *data++;
+
+    k *= m; 
+    k ^= k >> r; 
+    k *= m; 
+    
+    h ^= k;
+    h *= m; 
+  }
+
+  const unsigned char * data2 = (const unsigned char*)data;
+
+  switch(len & 7)
+  {
+  case 7: h ^= uint64_t(data2[6]) << 48;
+  case 6: h ^= uint64_t(data2[5]) << 40;
+  case 5: h ^= uint64_t(data2[4]) << 32;
+  case 4: h ^= uint64_t(data2[3]) << 24;
+  case 3: h ^= uint64_t(data2[2]) << 16;
+  case 2: h ^= uint64_t(data2[1]) << 8;
+  case 1: h ^= uint64_t(data2[0]);
+          h *= m;
+  };
+ 
+  h ^= h >> r;
+  h *= m;
+  h ^= h >> r;
+
+  return h;
+} 
+
+
+// 64-bit hash for 32-bit platforms
+
+uint64_t MurmurHash64B ( const void * key, size_t len, uint64_t seed )
+{
+  const uint32_t m = 0x5bd1e995;
+  const int r = 24;
+
+  uint32_t h1 = uint32_t(seed) ^ len;
+  uint32_t h2 = uint32_t(seed >> 32);
+
+  const uint32_t * data = (const uint32_t *)key;
+
+  while(len >= 8)
+  {
+    uint32_t k1 = *data++;
+    k1 *= m; k1 ^= k1 >> r; k1 *= m;
+    h1 *= m; h1 ^= k1;
+    len -= 4;
+
+    uint32_t k2 = *data++;
+    k2 *= m; k2 ^= k2 >> r; k2 *= m;
+    h2 *= m; h2 ^= k2;
+    len -= 4;
+  }
+
+  if(len >= 4)
+  {
+    uint32_t k1 = *data++;
+    k1 *= m; k1 ^= k1 >> r; k1 *= m;
+    h1 *= m; h1 ^= k1;
+    len -= 4;
+  }
+
+  switch(len)
+  {
+  case 3: h2 ^= ((unsigned char*)data)[2] << 16;
+  case 2: h2 ^= ((unsigned char*)data)[1] << 8;
+  case 1: h2 ^= ((unsigned char*)data)[0];
+      h2 *= m;
+  };
+
+  h1 ^= h2 >> 18; h1 *= m;
+  h2 ^= h1 >> 22; h2 *= m;
+  h1 ^= h2 >> 17; h1 *= m;
+  h2 ^= h1 >> 19; h2 *= m;
+
+  uint64_t h = h1;
+
+  h = (h << 32) | h2;
+
+  return h;
+} 
+
+//-----------------------------------------------------------------------------
+// MurmurHash2A, by Austin Appleby
+
+// This is a variant of MurmurHash2 modified to use the Merkle-Damgard 
+// construction. Bulk speed should be identical to Murmur2, small-key speed 
+// will be 10%-20% slower due to the added overhead at the end of the hash.
+
+// This variant fixes a minor issue where null keys were more likely to
+// collide with each other than expected, and also makes the function
+// more amenable to incremental implementations.
+
+#define mmix(h,k) { k *= m; k ^= k >> r; k *= m; h *= m; h ^= k; }
+
+uint32_t MurmurHash2A ( const void * key, size_t len, uint32_t seed )
+{
+  const uint32_t m = 0x5bd1e995;
+  const int r = 24;
+  uint32_t l = len;
+
+  const unsigned char * data = (const unsigned char *)key;
+
+  uint32_t h = seed;
+
+  while(len >= 4)
+  {
+    uint32_t k = *(uint32_t*)data;
+
+    mmix(h,k);
+
+    data += 4;
+    len -= 4;
+  }
+
+  uint32_t t = 0;
+
+  switch(len)
+  {
+  case 3: t ^= data[2] << 16;
+  case 2: t ^= data[1] << 8;
+  case 1: t ^= data[0];
+  };
+
+  mmix(h,t);
+  mmix(h,l);
+
+  h ^= h >> 13;
+  h *= m;
+  h ^= h >> 15;
+
+  return h;
+}
+
+//-----------------------------------------------------------------------------
+// CMurmurHash2A, by Austin Appleby
+
+// This is a sample implementation of MurmurHash2A designed to work 
+// incrementally.
+
+// Usage - 
+
+// CMurmurHash2A hasher
+// hasher.Begin(seed);
+// hasher.Add(data1,size1);
+// hasher.Add(data2,size2);
+// ...
+// hasher.Add(dataN,sizeN);
+// uint32_t hash = hasher.End()
+
+class CMurmurHash2A
+{
+public:
+
+  void Begin ( uint32_t seed = 0 )
+  {
+    m_hash  = seed;
+    m_tail  = 0;
+    m_count = 0;
+    m_size  = 0;
+  }
+
+  void Add ( const unsigned char * data, size_t len )
+  {
+    m_size += len;
+
+    MixTail(data,len);
+
+    while(len >= 4)
+    {
+      uint32_t k = *(uint32_t*)data;
+
+      mmix(m_hash,k);
+
+      data += 4;
+      len -= 4;
+    }
+
+    MixTail(data,len);
+  }
+
+  uint32_t End ( void )
+  {
+    mmix(m_hash,m_tail);
+    mmix(m_hash,m_size);
+
+    m_hash ^= m_hash >> 13;
+    m_hash *= m;
+    m_hash ^= m_hash >> 15;
+
+    return m_hash;
+  }
+
+private:
+
+  static const uint32_t m = 0x5bd1e995;
+  static const int r = 24;
+
+  void MixTail ( const unsigned char * & data, size_t & len )
+  {
+    while( len && ((len<4) || m_count) )
+    {
+      m_tail |= (*data++) << (m_count * 8);
+
+      m_count++;
+      len--;
+
+      if(m_count == 4)
+      {
+        mmix(m_hash,m_tail);
+        m_tail = 0;
+        m_count = 0;
+      }
+    }
+  }
+
+  uint32_t m_hash;
+  uint32_t m_tail;
+  uint32_t m_count;
+  uint32_t m_size;
+};
+
+//-----------------------------------------------------------------------------
+// MurmurHashNeutral2, by Austin Appleby
+
+// Same as MurmurHash2, but endian- and alignment-neutral.
+// Half the speed though, alas.
+
+uint32_t MurmurHashNeutral2 ( const void * key, size_t len, uint32_t seed )
+{
+  const uint32_t m = 0x5bd1e995;
+  const int r = 24;
+
+  uint32_t h = seed ^ len;
+
+  const unsigned char * data = (const unsigned char *)key;
+
+  while(len >= 4)
+  {
+    uint32_t k;
+
+    k  = data[0];
+    k |= data[1] << 8;
+    k |= data[2] << 16;
+    k |= data[3] << 24;
+
+    k *= m; 
+    k ^= k >> r; 
+    k *= m;
+
+    h *= m;
+    h ^= k;
+
+    data += 4;
+    len -= 4;
+  }
+  
+  switch(len)
+  {
+  case 3: h ^= data[2] << 16;
+  case 2: h ^= data[1] << 8;
+  case 1: h ^= data[0];
+          h *= m;
+  };
+
+  h ^= h >> 13;
+  h *= m;
+  h ^= h >> 15;
+
+  return h;
+} 
+
+//-----------------------------------------------------------------------------
+// MurmurHashAligned2, by Austin Appleby
+
+// Same algorithm as MurmurHash2, but only does aligned reads - should be safer
+// on certain platforms. 
+
+// Performance will be lower than MurmurHash2
+
+#define MIX(h,k,m) { k *= m; k ^= k >> r; k *= m; h *= m; h ^= k; }
+
+
+uint32_t MurmurHashAligned2 ( const void * key, size_t len, uint32_t seed )
+{
+  const uint32_t m = 0x5bd1e995;
+  const int r = 24;
+
+  const unsigned char * data = (const unsigned char *)key;
+
+  uint32_t h = seed ^ len;
+
+  size_t align = (uint64_t)data & 3;
+
+  if(align && (len >= 4))
+  {
+    // Pre-load the temp registers
+
+    uint32_t t = 0, d = 0;
+
+    switch(align)
+    {
+      case 1: t |= data[2] << 16;
+      case 2: t |= data[1] << 8;
+      case 3: t |= data[0];
+    }
+
+    t <<= (8 * align);
+
+    data += 4-align;
+    len -= 4-align;
+
+    int sl = 8 * (4-align);
+    int sr = 8 * align;
+
+    // Mix
+
+    while(len >= 4)
+    {
+      d = *(uint32_t *)data;
+      t = (t >> sr) | (d << sl);
+
+      uint32_t k = t;
+
+      MIX(h,k,m);
+
+      t = d;
+
+      data += 4;
+      len -= 4;
+    }
+
+    // Handle leftover data in temp registers
+
+    d = 0;
+
+    if(len >= align)
+    {
+      switch(align)
+      {
+      case 3: d |= data[2] << 16;
+      case 2: d |= data[1] << 8;
+      case 1: d |= data[0];
+      }
+
+      uint32_t k = (t >> sr) | (d << sl);
+      MIX(h,k,m);
+
+      data += align;
+      len -= align;
+
+      //----------
+      // Handle tail bytes
+
+      switch(len)
+      {
+      case 3: h ^= data[2] << 16;
+      case 2: h ^= data[1] << 8;
+      case 1: h ^= data[0];
+          h *= m;
+      };
+    }
+    else
+    {
+      switch(len)
+      {
+      case 3: d |= data[2] << 16;
+      case 2: d |= data[1] << 8;
+      case 1: d |= data[0];
+      case 0: h ^= (t >> sr) | (d << sl);
+          h *= m;
+      }
+    }
+
+    h ^= h >> 13;
+    h *= m;
+    h ^= h >> 15;
+
+    return h;
+  }
+  else
+  {
+    while(len >= 4)
+    {
+      uint32_t k = *(uint32_t *)data;
+
+      MIX(h,k,m);
+
+      data += 4;
+      len -= 4;
+    }
+
+    //----------
+    // Handle tail bytes
+
+    switch(len)
+    {
+    case 3: h ^= data[2] << 16;
+    case 2: h ^= data[1] << 8;
+    case 1: h ^= data[0];
+        h *= m;
+    };
+
+    h ^= h >> 13;
+    h *= m;
+    h ^= h >> 15;
+
+    return h;
+  }
+}
+
+//-----------------------------------------------------------------------------
+
--- a/contrib/murmurhash/src/MurmurHash3.cpp
+++ b/contrib/murmurhash/src/MurmurHash3.cpp
@ -1,3 +1,4 @@
+//-----------------------------------------------------------------------------
 // MurmurHash3 was written by Austin Appleby, and is placed in the public
 // domain. The author hereby disclaims copyright to this source code.

@ -6,8 +7,8 @@
 // compile and run any of them on any platform, but your performance with the
 // non-native version will be less than optimal.

-#include "murmurhash3.h"
-#include <cstring>
+#include "MurmurHash3.h"
+#include <string.h>

 //-----------------------------------------------------------------------------
 // Platform-specific functions and macros
@ -93,7 +94,7 @@ FORCE_INLINE uint64_t fmix64 ( uint64_t k )

 //-----------------------------------------------------------------------------

-void MurmurHash3_x86_32 ( const void * key, int len,
+void MurmurHash3_x86_32 ( const void * key, size_t len,
                          uint32_t seed, void * out )
 {
  const uint8_t * data = (const uint8_t*)key;
@ -149,7 +150,7 @@ void MurmurHash3_x86_32 ( const void * key, int len,

 //-----------------------------------------------------------------------------

-void MurmurHash3_x86_128 ( const void * key, const int len,
+void MurmurHash3_x86_128 ( const void * key, const size_t len,
                           uint32_t seed, void * out )
 {
  const uint8_t * data = (const uint8_t*)key;
@ -254,7 +255,7 @@ void MurmurHash3_x86_128 ( const void * key, const int len,

 //-----------------------------------------------------------------------------

-void MurmurHash3_x64_128 ( const void * key, const int len,
+void MurmurHash3_x64_128 ( const void * key, const size_t len,
                           const uint32_t seed, void * out )
 {
  const uint8_t * data = (const uint8_t*)key;
@ -332,3 +333,6 @@ void MurmurHash3_x64_128 ( const void * key, const int len,
  ((uint64_t*)out)[0] = h1;
  ((uint64_t*)out)[1] = h2;
 }
+
+//-----------------------------------------------------------------------------
+
--- a/contrib/murmurhash/src/murmurhash2.cpp
+++ b/contrib/murmurhash/src/murmurhash2.cpp
@ -1,423 +0,0 @@
-// MurmurHash2 was written by Austin Appleby, and is placed in the public
-// domain. The author hereby disclaims copyright to this source code.
-
-// Note - This code makes a few assumptions about how your machine behaves -
-
-// 1. We can read a 4-byte value from any address without crashing
-// 2. sizeof(int) == 4
-
-// And it has a few limitations -
-
-// 1. It will not work incrementally.
-// 2. It will not produce the same results on little-endian and big-endian
-//    machines.
-
-#include "murmurhash2.h"
-#include <cstring>
-
-// Platform-specific functions and macros
-// Microsoft Visual Studio
-
-#if defined(_MSC_VER)
-
-#define BIG_CONSTANT(x) (x)
-
-// Other compilers
-
-#else	// defined(_MSC_VER)
-
-#define BIG_CONSTANT(x) (x##LLU)
-
-#endif // !defined(_MSC_VER)
-
-
-uint32_t MurmurHash2(const void * key, int len, uint32_t seed)
-{
-    // 'm' and 'r' are mixing constants generated offline.
-    // They're not really 'magic', they just happen to work well.
-
-    const uint32_t m = 0x5bd1e995;
-    const int r = 24;
-
-    // Initialize the hash to a 'random' value
-
-    uint32_t h = seed ^ len;
-
-    // Mix 4 bytes at a time into the hash
-
-    const unsigned char * data = reinterpret_cast<const unsigned char *>(key);
-
-    while (len >= 4)
-    {
-        uint32_t k;
-        memcpy(&k, data, sizeof(k));
-        k *= m;
-        k ^= k >> r;
-        k *= m;
-
-        h *= m;
-        h ^= k;
-
-        data += 4;
-        len -= 4;
-    }
-
-    // Handle the last few bytes of the input array
- 
-    switch (len)
-    {
-        case 3: h ^= data[2] << 16;
-        case 2: h ^= data[1] << 8;
-        case 1: h ^= data[0];
-                h *= m;
-    };
-
-    // Do a few final mixes of the hash to ensure the last few
-    // bytes are well-incorporated.
-
-    h ^= h >> 13;
-    h *= m;
-    h ^= h >> 15;
-
-    return h;
-} 
-
-// MurmurHash2, 64-bit versions, by Austin Appleby
-
-// The same caveats as 32-bit MurmurHash2 apply here - beware of alignment 
-// and endian-ness issues if used across multiple platforms.
-
-// 64-bit hash for 64-bit platforms
-
-uint64_t MurmurHash64A(const void * key, int len, uint64_t seed)
-{
-    const uint64_t m = BIG_CONSTANT(0xc6a4a7935bd1e995);
-    const int r = 47;
-
-    uint64_t h = seed ^ (len * m);
-
-    const uint64_t * data = reinterpret_cast<const uint64_t *>(key);
-    const uint64_t * end = data + (len/8);
-
-    while (data != end)
-    {
-        uint64_t k = *data++;
-
-        k *= m; 
-        k ^= k >> r; 
-        k *= m; 
-
-        h ^= k;
-        h *= m; 
-    }
-
-    const unsigned char * data2 = reinterpret_cast<const unsigned char *>(data);
-
-    switch (len & 7)
-    {
-        case 7: h ^= static_cast<uint64_t>(data2[6]) << 48;
-        case 6: h ^= static_cast<uint64_t>(data2[5]) << 40;
-        case 5: h ^= static_cast<uint64_t>(data2[4]) << 32;
-        case 4: h ^= static_cast<uint64_t>(data2[3]) << 24;
-        case 3: h ^= static_cast<uint64_t>(data2[2]) << 16;
-        case 2: h ^= static_cast<uint64_t>(data2[1]) << 8;
-        case 1: h ^= static_cast<uint64_t>(data2[0]);
-                h *= m;
-    };
-
-    h ^= h >> r;
-    h *= m;
-    h ^= h >> r;
-
-    return h;
-} 
-
-
-// 64-bit hash for 32-bit platforms
-
-uint64_t MurmurHash64B(const void * key, int len, uint64_t seed)
-{
-    const uint32_t m = 0x5bd1e995;
-    const int r = 24;
-
-    uint32_t h1 = static_cast<uint32_t>(seed) ^ len;
-    uint32_t h2 = static_cast<uint32_t>(seed >> 32);
-
-    const uint32_t * data = reinterpret_cast<const uint32_t *>(key);
-
-    while (len >= 8)
-    {
-        uint32_t k1 = *data++;
-        k1 *= m; k1 ^= k1 >> r; k1 *= m;
-        h1 *= m; h1 ^= k1;
-        len -= 4;
-
-        uint32_t k2 = *data++;
-        k2 *= m; k2 ^= k2 >> r; k2 *= m;
-        h2 *= m; h2 ^= k2;
-        len -= 4;
-    }
-
-    if (len >= 4)
-    {
-        uint32_t k1 = *data++;
-        k1 *= m; k1 ^= k1 >> r; k1 *= m;
-        h1 *= m; h1 ^= k1;
-        len -= 4;
-    }
-
-    switch (len)
-    {
-        case 3: h2 ^= reinterpret_cast<const unsigned char *>(data)[2] << 16;
-        case 2: h2 ^= reinterpret_cast<const unsigned char *>(data)[1] << 8;
-        case 1: h2 ^= reinterpret_cast<const unsigned char *>(data)[0];
-                h2 *= m;
-    };
-
-    h1 ^= h2 >> 18; h1 *= m;
-    h2 ^= h1 >> 22; h2 *= m;
-    h1 ^= h2 >> 17; h1 *= m;
-    h2 ^= h1 >> 19; h2 *= m;
-
-    uint64_t h = h1;
-
-    h = (h << 32) | h2;
-
-    return h;
-} 
-
-// MurmurHash2A, by Austin Appleby
-
-// This is a variant of MurmurHash2 modified to use the Merkle-Damgard 
-// construction. Bulk speed should be identical to Murmur2, small-key speed 
-// will be 10%-20% slower due to the added overhead at the end of the hash.
-
-// This variant fixes a minor issue where null keys were more likely to
-// collide with each other than expected, and also makes the function
-// more amenable to incremental implementations.
-
-#define mmix(h,k) { k *= m; k ^= k >> r; k *= m; h *= m; h ^= k; }
-
-uint32_t MurmurHash2A(const void * key, int len, uint32_t seed)
-{
-    const uint32_t m = 0x5bd1e995;
-    const int r = 24;
-    uint32_t l = len;
-
-    const unsigned char * data = reinterpret_cast<const unsigned char *>(key);
-
-    uint32_t h = seed;
-
-    while (len >= 4)
-    {
-        uint32_t k = *reinterpret_cast<const uint32_t *>(data);
-        mmix(h,k);
-        data += 4;
-        len -= 4;
-    }
-
-    uint32_t t = 0;
-
-    switch (len)
-    {
-        case 3: t ^= data[2] << 16;
-        case 2: t ^= data[1] << 8;
-        case 1: t ^= data[0];
-    };
-
-    mmix(h,t);
-    mmix(h,l);
-
-    h ^= h >> 13;
-    h *= m;
-    h ^= h >> 15;
-
-    return h;
-}
-
-// MurmurHashNeutral2, by Austin Appleby
-
-// Same as MurmurHash2, but endian- and alignment-neutral.
-// Half the speed though, alas.
-
-uint32_t MurmurHashNeutral2(const void * key, int len, uint32_t seed)
-{
-    const uint32_t m = 0x5bd1e995;
-    const int r = 24;
-
-    uint32_t h = seed ^ len;
-
-    const unsigned char * data = reinterpret_cast<const unsigned char *>(key);
-
-    while (len >= 4)
-    {
-        uint32_t k;
-
-        k  = data[0];
-        k |= data[1] << 8;
-        k |= data[2] << 16;
-        k |= data[3] << 24;
-
-        k *= m; 
-        k ^= k >> r; 
-        k *= m;
-
-        h *= m;
-        h ^= k;
-
-        data += 4;
-        len -= 4;
-    }
-
-    switch (len)
-    {
-        case 3: h ^= data[2] << 16;
-        case 2: h ^= data[1] << 8;
-        case 1: h ^= data[0];
-                h *= m;
-    };
-
-    h ^= h >> 13;
-    h *= m;
-    h ^= h >> 15;
-
-    return h;
-} 
-
-//-----------------------------------------------------------------------------
-// MurmurHashAligned2, by Austin Appleby
-
-// Same algorithm as MurmurHash2, but only does aligned reads - should be safer
-// on certain platforms. 
-
-// Performance will be lower than MurmurHash2
-
-#define MIX(h,k,m) { k *= m; k ^= k >> r; k *= m; h *= m; h ^= k; }
-
-
-uint32_t MurmurHashAligned2(const void * key, int len, uint32_t seed)
-{
-    const uint32_t m = 0x5bd1e995;
-    const int r = 24;
-
-    const unsigned char * data = reinterpret_cast<const unsigned char *>(key);
-
-    uint32_t h = seed ^ len;
-
-    int align = reinterpret_cast<uint64_t>(data) & 3;
-
-    if (align && (len >= 4))
-    {
-        // Pre-load the temp registers
-
-        uint32_t t = 0, d = 0;
-
-        switch (align)
-        {
-            case 1: t |= data[2] << 16;
-            case 2: t |= data[1] << 8;
-            case 3: t |= data[0];
-        }
-
-        t <<= (8 * align);
-
-        data += 4-align;
-        len -= 4-align;
-
-        int sl = 8 * (4-align);
-        int sr = 8 * align;
-
-        // Mix
-
-        while (len >= 4)
-        {
-            d = *(reinterpret_cast<const uint32_t *>(data));
-            t = (t >> sr) | (d << sl);
-
-            uint32_t k = t;
-
-            MIX(h,k,m);
-
-            t = d;
-
-            data += 4;
-            len -= 4;
-        }
-
-        // Handle leftover data in temp registers
-
-        d = 0;
-
-        if (len >= align)
-        {
-            switch (align)
-            {
-                case 3: d |= data[2] << 16;
-                case 2: d |= data[1] << 8;
-                case 1: d |= data[0];
-            }
-
-            uint32_t k = (t >> sr) | (d << sl);
-            MIX(h,k,m);
-
-            data += align;
-            len -= align;
-
-            //----------
-            // Handle tail bytes
-
-            switch (len)
-            {
-                case 3: h ^= data[2] << 16;
-                case 2: h ^= data[1] << 8;
-                case 1: h ^= data[0];
-                        h *= m;
-            };
-        }
-        else
-        {
-            switch (len)
-            {
-                case 3: d |= data[2] << 16;
-                case 2: d |= data[1] << 8;
-                case 1: d |= data[0];
-                case 0: h ^= (t >> sr) | (d << sl);
-                        h *= m;
-            }
-        }
-
-        h ^= h >> 13;
-        h *= m;
-        h ^= h >> 15;
-
-        return h;
-    }
-    else
-    {
-        while (len >= 4)
-        {
-            uint32_t k = *reinterpret_cast<const uint32_t *>(data);
-
-            MIX(h,k,m);
-
-            data += 4;
-            len -= 4;
-        }
-
-        // Handle tail bytes
-
-        switch (len)
-        {
-            case 3: h ^= data[2] << 16;
-            case 2: h ^= data[1] << 8;
-            case 1: h ^= data[0];
-                    h *= m;
-        };
-
-        h ^= h >> 13;
-        h *= m;
-        h ^= h >> 15;
-
-        return h;
-  }
-}
--- a/debian/changelog
+++ b/debian/changelog
@ -1,5 +1,5 @@
-clickhouse (21.7.1.1) unstable; urgency=low
+clickhouse (21.8.1.1) unstable; urgency=low

  * Modified source code

- -- clickhouse-release <clickhouse-release@yandex-team.ru>  Thu, 20 May 2021 22:23:29 +0300
+ -- clickhouse-release <clickhouse-release@yandex-team.ru>  Mon, 28 Jun 2021 00:50:15 +0300
--- a/docker/client/Dockerfile
+++ b/docker/client/Dockerfile
@ -1,7 +1,7 @@
 FROM ubuntu:18.04

 ARG repository="deb https://repo.clickhouse.tech/deb/stable/ main/"
-ARG version=21.7.1.*
+ARG version=21.8.1.*

 RUN apt-get update \
    && apt-get install --yes --no-install-recommends \
--- a/docker/packager/binary/Dockerfile
+++ b/docker/packager/binary/Dockerfile
@ -72,7 +72,7 @@ RUN git clone https://github.com/tpoechtrager/apple-libtapi.git \
    && cd .. \
    && rm -rf apple-libtapi

-# Build and install tools for cross-linking to Darwin
+# Build and install tools for cross-linking to Darwin (x86-64)
 RUN git clone https://github.com/tpoechtrager/cctools-port.git \
    && cd cctools-port/cctools \
    && ./configure --prefix=/cctools --with-libtapi=/cctools \
@ -81,8 +81,17 @@ RUN git clone https://github.com/tpoechtrager/cctools-port.git \
    && cd ../.. \
    && rm -rf cctools-port

-# Download toolchain for Darwin
-RUN wget -nv https://github.com/phracker/MacOSX-SDKs/releases/download/10.15/MacOSX10.15.sdk.tar.xz
+# Build and install tools for cross-linking to Darwin (aarch64)
+RUN git clone https://github.com/tpoechtrager/cctools-port.git \
+    && cd cctools-port/cctools \
+    && ./configure --prefix=/cctools --with-libtapi=/cctools \
+        --target=aarch64-apple-darwin \
+    && make install \
+    && cd ../.. \
+    && rm -rf cctools-port
+
+# Download toolchain and SDK for Darwin
+RUN wget -nv https://github.com/phracker/MacOSX-SDKs/releases/download/11.3/MacOSX11.0.sdk.tar.xz

 # Download toolchain for ARM
 # It contains all required headers and libraries. Note that it's named as "gcc" but actually we are using clang for cross compiling.
--- a/docker/packager/binary/build.sh
+++ b/docker/packager/binary/build.sh
@ -3,7 +3,9 @@
 set -x -e

 mkdir -p build/cmake/toolchain/darwin-x86_64
-tar xJf MacOSX10.15.sdk.tar.xz -C build/cmake/toolchain/darwin-x86_64 --strip-components=1
+tar xJf MacOSX11.0.sdk.tar.xz -C build/cmake/toolchain/darwin-x86_64 --strip-components=1
+
+ln -sf darwin-x86_64 build/cmake/toolchain/darwin-aarch64

 mkdir -p build/cmake/toolchain/linux-aarch64
 tar xJf gcc-arm-8.3-2019.03-x86_64-aarch64-linux-gnu.tar.xz -C build/cmake/toolchain/linux-aarch64 --strip-components=1
--- a/docker/packager/packager
+++ b/docker/packager/packager
@ -58,6 +58,7 @@ def run_docker_image_with_env(image_name, output, env_variables, ch_root, ccache
 def parse_env_variables(build_type, compiler, sanitizer, package_type, image_type, cache, distcc_hosts, unbundled, split_binary, clang_tidy, version, author, official, alien_pkgs, with_coverage, with_binaries):
    CLANG_PREFIX = "clang"
    DARWIN_SUFFIX = "-darwin"
+    DARWIN_ARM_SUFFIX = "-darwin-aarch64"
    ARM_SUFFIX = "-aarch64"
    FREEBSD_SUFFIX = "-freebsd"

@ -66,9 +67,10 @@ def parse_env_variables(build_type, compiler, sanitizer, package_type, image_typ

    is_clang = compiler.startswith(CLANG_PREFIX)
    is_cross_darwin = compiler.endswith(DARWIN_SUFFIX)
+    is_cross_darwin_arm = compiler.endswith(DARWIN_ARM_SUFFIX)
    is_cross_arm = compiler.endswith(ARM_SUFFIX)
    is_cross_freebsd = compiler.endswith(FREEBSD_SUFFIX)
-    is_cross_compile = is_cross_darwin or is_cross_arm or is_cross_freebsd
+    is_cross_compile = is_cross_darwin or is_cross_darwin_arm or is_cross_arm or is_cross_freebsd

    # Explicitly use LLD with Clang by default.
    # Don't force linker for cross-compilation.
@ -82,6 +84,13 @@ def parse_env_variables(build_type, compiler, sanitizer, package_type, image_typ
        cmake_flags.append("-DCMAKE_RANLIB:FILEPATH=/cctools/bin/x86_64-apple-darwin-ranlib")
        cmake_flags.append("-DLINKER_NAME=/cctools/bin/x86_64-apple-darwin-ld")
        cmake_flags.append("-DCMAKE_TOOLCHAIN_FILE=/build/cmake/darwin/toolchain-x86_64.cmake")
+    elif is_cross_darwin_arm:
+        cc = compiler[:-len(DARWIN_ARM_SUFFIX)]
+        cmake_flags.append("-DCMAKE_AR:FILEPATH=/cctools/bin/aarch64-apple-darwin-ar")
+        cmake_flags.append("-DCMAKE_INSTALL_NAME_TOOL=/cctools/bin/aarch64-apple-darwin-install_name_tool")
+        cmake_flags.append("-DCMAKE_RANLIB:FILEPATH=/cctools/bin/aarch64-apple-darwin-ranlib")
+        cmake_flags.append("-DLINKER_NAME=/cctools/bin/aarch64-apple-darwin-ld")
+        cmake_flags.append("-DCMAKE_TOOLCHAIN_FILE=/build/cmake/darwin/toolchain-aarch64.cmake")
    elif is_cross_arm:
        cc = compiler[:-len(ARM_SUFFIX)]
        cmake_flags.append("-DCMAKE_TOOLCHAIN_FILE=/build/cmake/linux/toolchain-aarch64.cmake")
@ -185,8 +194,8 @@ if __name__ == "__main__":
    parser.add_argument("--clickhouse-repo-path", default=os.path.join(os.path.dirname(os.path.abspath(__file__)), os.pardir, os.pardir))
    parser.add_argument("--output-dir", required=True)
    parser.add_argument("--build-type", choices=("debug", ""), default="")
-    parser.add_argument("--compiler", choices=("clang-11", "clang-11-darwin", "clang-11-aarch64", "clang-11-freebsd",
-                                               "gcc-10"), default="clang-11")
+    parser.add_argument("--compiler", choices=("clang-11", "clang-11-darwin", "clang-11-darwin-aarch64", "clang-11-aarch64",
+                                               "clang-11-freebsd", "gcc-10"), default="clang-11")
    parser.add_argument("--sanitizer", choices=("address", "thread", "memory", "undefined", ""), default="")
    parser.add_argument("--unbundled", action="store_true")
    parser.add_argument("--split-binary", action="store_true")
--- a/docker/server/Dockerfile
+++ b/docker/server/Dockerfile
@ -1,7 +1,7 @@
 FROM ubuntu:20.04

 ARG repository="deb https://repo.clickhouse.tech/deb/stable/ main/"
-ARG version=21.7.1.*
+ARG version=21.8.1.*
 ARG gosu_ver=1.10

 # set non-empty deb_location_url url to create a docker image
--- a/docker/test/Dockerfile
+++ b/docker/test/Dockerfile
@ -1,7 +1,7 @@
 FROM ubuntu:18.04

 ARG repository="deb https://repo.clickhouse.tech/deb/stable/ main/"
-ARG version=21.7.1.*
+ARG version=21.8.1.*

 RUN apt-get update && \
    apt-get install -y apt-transport-https dirmngr && \
--- a/docker/test/fasttest/run.sh
+++ b/docker/test/fasttest/run.sh
@ -113,6 +113,7 @@ function start_server
    echo "ClickHouse server pid '$server_pid' started and responded"

    echo "
+set follow-fork-mode child
 handle all noprint
 handle SIGSEGV stop print
 handle SIGBUS stop print
--- a/docker/test/fuzzer/run-fuzzer.sh
+++ b/docker/test/fuzzer/run-fuzzer.sh
@ -103,6 +103,7 @@ function fuzz
    kill -0 $server_pid

    echo "
+set follow-fork-mode child
 handle all noprint
 handle SIGSEGV stop print
 handle SIGBUS stop print
--- a/docker/test/performance-comparison/compare.sh
+++ b/docker/test/performance-comparison/compare.sh
@ -409,10 +409,10 @@ create view right_query_log as select *
        '$(cat "right-query-log.tsv.columns")');

 create view query_logs as
-    select 0 version, query_id, ProfileEvents.Names, ProfileEvents.Values,
+    select 0 version, query_id, ProfileEvents.keys, ProfileEvents.values,
        query_duration_ms, memory_usage from left_query_log
    union all
-    select 1 version, query_id, ProfileEvents.Names, ProfileEvents.Values,
+    select 1 version, query_id, ProfileEvents.keys, ProfileEvents.values,
        query_duration_ms, memory_usage from right_query_log
    ;

@ -424,7 +424,7 @@ create table query_run_metric_arrays engine File(TSV, 'analyze/query-run-metric-
    with (
        -- sumMapState with the list of all keys with '-0.' values. Negative zero is because
        -- sumMap removes keys with positive zeros.
-        with (select groupUniqArrayArray(ProfileEvents.Names) from query_logs) as all_names
+        with (select groupUniqArrayArray(ProfileEvents.keys) from query_logs) as all_names
            select arrayReduce('sumMapState', [(all_names, arrayMap(x->-0., all_names))])
        ) as all_metrics
    select test, query_index, version, query_id,
@ -433,8 +433,8 @@ create table query_run_metric_arrays engine File(TSV, 'analyze/query-run-metric-
                [
                    all_metrics,
                    arrayReduce('sumMapState',
-                        [(ProfileEvents.Names,
-                            arrayMap(x->toFloat64(x), ProfileEvents.Values))]
+                        [(ProfileEvents.keys,
+                            arrayMap(x->toFloat64(x), ProfileEvents.values))]
                    ),
                    arrayReduce('sumMapState', [(
                        ['client_time', 'server_time', 'memory_usage'],
@ -1005,7 +1005,7 @@ create table unstable_run_metrics engine File(TSVWithNamesAndTypes,
        'unstable-run-metrics.$version.rep') as
    select
        test, query_index, query_id,
-        ProfileEvents.Values value, ProfileEvents.Names metric
+        ProfileEvents.values value, ProfileEvents.keys metric
    from query_log array join ProfileEvents
    join unstable_query_runs using (query_id)
    ;
--- a/docker/test/performance-comparison/report.py
+++ b/docker/test/performance-comparison/report.py
@ -561,7 +561,7 @@ if args.report == 'main':
    # Don't show mildly unstable queries, only the very unstable ones we
    # treat as errors.
    if very_unstable_queries:
-        if very_unstable_queries > 3:
+        if very_unstable_queries > 5:
            error_tests += very_unstable_queries
            status = 'failure'
        message_array.append(str(very_unstable_queries) + ' unstable')
--- a/docker/test/stress/run.sh
+++ b/docker/test/stress/run.sh
@ -55,6 +55,7 @@ function start()
    done

    echo "
+set follow-fork-mode child
 handle all noprint
 handle SIGSEGV stop print
 handle SIGBUS stop print
--- a/docs/_includes/cmake_in_clickhouse_header.md
+++ b/docs/_includes/cmake_in_clickhouse_header.md
@ -2,18 +2,16 @@

 ## TL; DR How to make ClickHouse compile and link faster?

-Developer only! This command will likely fulfill most of your needs. Run before calling `ninja`.
+Minimal ClickHouse build example:

-```cmake
+```bash
 cmake .. \
-    -DCMAKE_C_COMPILER=/bin/clang-10 \
-    -DCMAKE_CXX_COMPILER=/bin/clang++-10 \
+    -DCMAKE_C_COMPILER=$(which clang-11) \
+    -DCMAKE_CXX_COMPILER=$(which clang++-11) \
    -DCMAKE_BUILD_TYPE=Debug \
    -DENABLE_CLICKHOUSE_ALL=OFF \
    -DENABLE_CLICKHOUSE_SERVER=ON \
    -DENABLE_CLICKHOUSE_CLIENT=ON \
-    -DUSE_STATIC_LIBRARIES=OFF \
-    -DSPLIT_SHARED_LIBRARIES=ON \
    -DENABLE_LIBRARIES=OFF \
    -DUSE_UNWIND=ON \
    -DENABLE_UTILS=OFF \
--- a/docs/en/development/build-osx.md
+++ b/docs/en/development/build-osx.md
@ -33,7 +33,7 @@ Reboot.

 ``` bash
 brew update
-brew install cmake ninja libtool gettext llvm gcc
+brew install cmake ninja libtool gettext llvm gcc binutils
 ```

 ## Checkout ClickHouse Sources {#checkout-clickhouse-sources}
--- a/docs/en/development/continuous-integration.md
+++ b/docs/en/development/continuous-integration.md
@ -126,7 +126,7 @@ Builds ClickHouse in various configurations for use in further steps. You have t
 - **Compiler**: `gcc-9` or `clang-10` (or `clang-10-xx` for other architectures e.g. `clang-10-freebsd`).
 - **Build type**: `Debug` or `RelWithDebInfo` (cmake).
 - **Sanitizer**: `none` (without sanitizers), `address` (ASan), `memory` (MSan), `undefined` (UBSan), or `thread` (TSan).
- **Bundled**: `bundled` build uses system libraries, and `unbundled` build uses libraries from `contrib` folder.
+- **Bundled**: `bundled` build uses libraries from `contrib` folder, and `unbundled` build uses system libraries.
 - **Splitted** `splitted` is a [split build](build.md#split-build)
 - **Status**: `success` or `fail`
 - **Build log**: link to the building and files copying log, useful when build failed.
--- a/docs/en/engines/database-engines/materialize-mysql.md
+++ b/docs/en/engines/database-engines/materialize-mysql.md
@ -49,6 +49,7 @@ When working with the `MaterializeMySQL` database engine, [ReplacingMergeTree](.
 | DATE, NEWDATE           | [Date](../../sql-reference/data-types/date.md)               |
 | DATETIME, TIMESTAMP     | [DateTime](../../sql-reference/data-types/datetime.md)       |
 | DATETIME2, TIMESTAMP2   | [DateTime64](../../sql-reference/data-types/datetime64.md)   |
+| ENUM                    | [Enum](../../sql-reference/data-types/enum.md)               |
 | STRING                  | [String](../../sql-reference/data-types/string.md)           |
 | VARCHAR, VAR_STRING     | [String](../../sql-reference/data-types/string.md)           |
 | BLOB                    | [String](../../sql-reference/data-types/string.md)           |
--- a/docs/en/engines/table-engines/integrations/ExternalDistributed.md
+++ b/docs/en/engines/table-engines/integrations/ExternalDistributed.md
@ -0,0 +1,53 @@
+---
+toc_priority: 12
+toc_title: ExternalDistributed
+---
+
+# ExternalDistributed {#externaldistributed}
+
+The `ExternalDistributed` engine allows to perform `SELECT` queries on data that is stored on a remote servers MySQL or PostgreSQL. Accepts [MySQL](../../../engines/table-engines/integrations/mysql.md) or [PostgreSQL](../../../engines/table-engines/integrations/postgresql.md) engines as an argument so sharding is possible.
+
+## Creating a Table {#creating-a-table}
+
+``` sql
+CREATE TABLE [IF NOT EXISTS] [db.]table_name [ON CLUSTER cluster]
+(
+    name1 [type1] [DEFAULT|MATERIALIZED|ALIAS expr1] [TTL expr1],
+    name2 [type2] [DEFAULT|MATERIALIZED|ALIAS expr2] [TTL expr2],
+    ...
+) ENGINE = ExternalDistributed('engine', 'host:port', 'database', 'table', 'user', 'password');
+```
+
+See a detailed description of the [CREATE TABLE](../../../sql-reference/statements/create/table.md#create-table-query) query.
+
+The table structure can differ from the original table structure:
+
+-   Column names should be the same as in the original table, but you can use just some of these columns and in any order.
+-   Column types may differ from those in the original table. ClickHouse tries to [cast](../../../sql-reference/functions/type-conversion-functions.md#type_conversion_function-cast) values to the ClickHouse data types.
+
+**Engine Parameters**
+
+-   `engine` — The table engine `MySQL` or `PostgreSQL`.
+-   `host:port` — MySQL or PostgreSQL server address.
+-   `database` — Remote database name.
+-   `table` — Remote table name.
+-   `user` — User name.
+-   `password` — User password.
+
+## Implementation Details {#implementation-details}
+	
+Supports multiple replicas that must be listed by `|` and shards must be listed by `,`. For example:
+
+```sql
+CREATE TABLE test_shards (id UInt32, name String, age UInt32, money UInt32) ENGINE = ExternalDistributed('MySQL', `mysql{1|2}:3306,mysql{3|4}:3306`, 'clickhouse', 'test_replicas', 'root', 'clickhouse');
+```
+
+When specifying replicas, one of the available replicas is selected for each of the shards when reading. If the connection fails, the next replica is selected, and so on for all the replicas. If the connection attempt fails for all the replicas, the attempt is repeated the same way several times.
+
+You can specify any number of shards and any number of replicas for each shard.
+
+**See Also**
+
+-   [MySQL table engine](../../../engines/table-engines/integrations/mysql.md)
+-   [PostgreSQL table engine](../../../engines/table-engines/integrations/postgresql.md)
+-   [Distributed table engine](../../../engines/table-engines/special/distributed.md)
--- a/docs/en/engines/table-engines/integrations/mysql.md
+++ b/docs/en/engines/table-engines/integrations/mysql.md
@ -28,8 +28,8 @@ See a detailed description of the [CREATE TABLE](../../../sql-reference/statemen
 The table structure can differ from the original MySQL table structure:

 -   Column names should be the same as in the original MySQL table, but you can use just some of these columns and in any order.
-   Column types may differ from those in the original MySQL table. ClickHouse tries to [cast](../../../sql-reference/functions/type-conversion-functions.md#type_conversion_function-cast) values to the ClickHouse data types.
-   Setting `external_table_functions_use_nulls` defines how to handle Nullable columns. Default is true, if false - table function will not make nullable columns and will insert default values instead of nulls. This is also applicable for null values inside array data types.
+-   Column types may differ from those in the original MySQL table. ClickHouse tries to [cast](../../../engines/database-engines/mysql.md#data_types-support) values to the ClickHouse data types.
+-   The [external_table_functions_use_nulls](../../../operations/settings/settings.md#external-table-functions-use-nulls) setting defines how to handle Nullable columns. Default value: 1. If 0, the table function does not make Nullable columns and inserts default values instead of nulls. This is also applicable for NULL values inside arrays.

 **Engine Parameters**

@ -55,6 +55,12 @@ Simple `WHERE` clauses such as `=, !=, >, >=, <, <=` are executed on the MySQL s

 The rest of the conditions and the `LIMIT` sampling constraint are executed in ClickHouse only after the query to MySQL finishes.

+Supports multiple replicas that must be listed by `|`. For example:
+
+```sql
+CREATE TABLE test_replicas (id UInt32, name String, age UInt32, money UInt32) ENGINE = MySQL(`mysql{2|3|4}:3306`, 'clickhouse', 'test_replicas', 'root', 'clickhouse');
+```
+
 ## Usage Example {#usage-example}

 Table in MySQL:
--- a/docs/en/engines/table-engines/integrations/odbc.md
+++ b/docs/en/engines/table-engines/integrations/odbc.md
@ -29,7 +29,7 @@ The table structure can differ from the source table structure:

 -   Column names should be the same as in the source table, but you can use just some of these columns and in any order.
 -   Column types may differ from those in the source table. ClickHouse tries to [cast](../../../sql-reference/functions/type-conversion-functions.md#type_conversion_function-cast) values to the ClickHouse data types.
-   Setting `external_table_functions_use_nulls` defines how to handle Nullable columns. Default is true, if false - table function will not make nullable columns and will insert default values instead of nulls. This is also applicable for null values inside array data types.
+-   The [external_table_functions_use_nulls](../../../operations/settings/settings.md#external-table-functions-use-nulls) setting defines how to handle Nullable columns. Default value: 1. If 0, the table function does not make Nullable columns and inserts default values instead of nulls. This is also applicable for NULL values inside arrays.

 **Engine Parameters**

--- a/docs/en/engines/table-engines/integrations/postgresql.md
+++ b/docs/en/engines/table-engines/integrations/postgresql.md
@ -23,8 +23,8 @@ See a detailed description of the [CREATE TABLE](../../../sql-reference/statemen
 The table structure can differ from the original PostgreSQL table structure:

 -   Column names should be the same as in the original PostgreSQL table, but you can use just some of these columns and in any order.
-   Column types may differ from those in the original PostgreSQL table. ClickHouse tries to [cast](../../../sql-reference/functions/type-conversion-functions.md#type_conversion_function-cast) values to the ClickHouse data types.
-   Setting `external_table_functions_use_nulls` defines how to handle Nullable columns. Default is 1, if 0 - table function will not make nullable columns and will insert default values instead of nulls. This is also applicable for null values inside array data types.
+-   Column types may differ from those in the original PostgreSQL table. ClickHouse tries to [cast](../../../engines/database-engines/postgresql.md#data_types-support) values to the ClickHouse data types.
+-   The [external_table_functions_use_nulls](../../../operations/settings/settings.md#external-table-functions-use-nulls) setting defines how to handle Nullable columns. Default value: 1. If 0, the table function does not make Nullable columns and inserts default values instead of nulls. This is also applicable for NULL values inside arrays.

 **Engine Parameters**

@ -50,6 +50,12 @@ PostgreSQL `Array` types are converted into ClickHouse arrays.
 !!! info "Note"
    Be careful - in PostgreSQL an array data, created like a `type_name[]`, may contain multi-dimensional arrays of different dimensions in different table rows in same column. But in ClickHouse it is only allowed to have multidimensional arrays of the same count of dimensions in all table rows in same column.
 	
+Supports multiple replicas that must be listed by `|`. For example:
+
+```sql
+CREATE TABLE test_replicas (id UInt32, name String) ENGINE = PostgreSQL(`postgres{2|3|4}:5432`, 'clickhouse', 'test_replicas', 'postgres', 'mysecretpassword');
+```
+
 Replicas priority for PostgreSQL dictionary source is supported. The bigger the number in map, the less the priority. The highest priority is `0`. 

 In the example below replica `example01-1` has the highest priority:
--- a/docs/en/getting-started/example-datasets/recipes.md
+++ b/docs/en/getting-started/example-datasets/recipes.md
@ -65,7 +65,7 @@ By checking the row count:

 Query:

-``` sq;
+``` sql
 SELECT count() FROM recipes;
 ```

--- a/docs/en/interfaces/formats.md
+++ b/docs/en/interfaces/formats.md
@ -1302,6 +1302,7 @@ The table below shows supported data types and how they match ClickHouse [data t
 | `STRING`, `BINARY`         | [String](../sql-reference/data-types/string.md)     | `UTF8`                     |
 | `STRING`, `BINARY`         | [FixedString](../sql-reference/data-types/fixedstring.md)   | `UTF8`                        |
 | `DECIMAL`                  | [Decimal](../sql-reference/data-types/decimal.md)   | `DECIMAL`                  |
+| `DECIMAL256`               | [Decimal256](../sql-reference/data-types/decimal.md)| `DECIMAL256`               |
 | `LIST`                     | [Array](../sql-reference/data-types/array.md)       | `LIST`                     |

 Arrays can be nested and can have a value of the `Nullable` type as an argument.
--- a/docs/en/introduction/adopters.md
+++ b/docs/en/introduction/adopters.md
@ -148,5 +148,11 @@ toc_title: Adopters
 | <a href="https://www.kakaocorp.com/" class="favicon">kakaocorp</a> | Internet company | — | — | — | [if(kakao)2020 conference](https://if.kakao.com/session/117) |
 | <a href="https://shop.okraina.ru/" class="favicon">ООО «МПЗ Богородский»</a> | Agriculture | — | — | — | [Article in Russian, November 2020](https://cloud.yandex.ru/cases/okraina) |
 | <a href="https://www.tesla.com/" class="favicon">Tesla</a> | Electric vehicle and clean energy company | — | — | — | [Vacancy description, March 2021](https://news.ycombinator.com/item?id=26306170) |
+| <a href="https://www.kgk-global.com/en/" class="favicon">KGK Global</a> | Vehicle monitoring | — | — | — | [Press release, June 2021](https://zoom.cnews.ru/news/item/530921) |
+| <a href="https://www.bilibili.com/" class="favicon">BiliBili</a> | Video sharing | — | — | — | [Blog post, June 2021](https://chowdera.com/2021/06/20210622012241476b.html) |
+| <a href="https://gigapipe.com/" class="favicon">Gigapipe</a> | Managed ClickHouse | Main product | — | — | [Official website](https://gigapipe.com/) |
+| <a href="https://www.hydrolix.io/" class="favicon">Hydrolix</a> | Cloud data platform | Main product | — | — | [Documentation](https://docs.hydrolix.io/guide/query) |
+| <a href="https://www.argedor.com/en/clickhouse/" class="favicon">Argedor</a> | ClickHouse support | — | — | — | [Official website](https://www.argedor.com/en/clickhouse/) |
+| <a href="https://signoz.io/" class="favicon">SigNoz</a> | Observability Platform | Main Product | — | — | [Source code](https://github.com/SigNoz/signoz) |

 [Original article](https://clickhouse.tech/docs/en/introduction/adopters/) <!--hide-->
--- a/docs/en/operations/settings/settings.md
+++ b/docs/en/operations/settings/settings.md
@ -1194,21 +1194,22 @@ This setting is useful for replicated tables with a sampling key. A query may be
 !!! warning "Warning"
    This setting will produce incorrect results when joins or subqueries are involved, and all tables don't meet certain requirements. See [Distributed Subqueries and max_parallel_replicas](../../sql-reference/operators/in.md#max_parallel_replica-subqueries) for more details.

-## compile {#compile}
+## compile_expressions {#compile-expressions}

-Enable compilation of queries. By default, 0 (disabled).
+Enables or disables compilation of frequently used simple functions and operators to native code with LLVM at runtime.

-The compilation is only used for part of the query-processing pipeline: for the first stage of aggregation (GROUP BY).
-If this portion of the pipeline was compiled, the query may run faster due to the deployment of short cycles and inlining aggregate function calls. The maximum performance improvement (up to four times faster in rare cases) is seen for queries with multiple simple aggregate functions. Typically, the performance gain is insignificant. In very rare cases, it may slow down query execution.
+Possible values:

-## min_count_to_compile {#min-count-to-compile}
+- 0 — Disabled.
+- 1 — Enabled.

-How many times to potentially use a compiled chunk of code before running compilation. By default, 3.
-For testing, the value can be set to 0: compilation runs synchronously and the query waits for the end of the compilation process before continuing execution. For all other cases, use values starting with 1. Compilation normally takes about 5-10 seconds.
-If the value is 1 or more, compilation occurs asynchronously in a separate thread. The result will be used as soon as it is ready, including queries that are currently running.
+Default value: `1`.

-Compiled code is required for each different combination of aggregate functions used in the query and the type of keys in the GROUP BY clause.
-The results of the compilation are saved in the build directory in the form of .so files. There is no restriction on the number of compilation results since they do not use very much space. Old results will be used after server restarts, except in the case of a server upgrade – in this case, the old results are deleted.
+## min_count_to_compile_expression {#min-count-to-compile-expression}
+
+Minimum count of executing same expression before it is get compiled.
+
+Default value: `3`.

 ## output_format_json_quote_64bit_integers {#session_settings-output_format_json_quote_64bit_integers}

@ -1558,7 +1559,7 @@ Possible values:

 -   0 — Disabled (final query processing is done on the initiator node).
 -   1 - Do not merge aggregation states from different servers for distributed query processing (query completelly processed on the shard, initiator only proxy the data), can be used in case it is for certain that there are different keys on different shards.
-   2 - Same as `1` but applies `ORDER BY` and `LIMIT` (it is not possilbe when the query processed completelly on the remote node, like for `distributed_group_by_no_merge=1`) on the initiator (can be used for queries with `ORDER BY` and/or `LIMIT`).
+-   2 - Same as `1` but applies `ORDER BY` and `LIMIT` (it is not possible when the query processed completelly on the remote node, like for `distributed_group_by_no_merge=1`) on the initiator (can be used for queries with `ORDER BY` and/or `LIMIT`).

 **Example**

@ -1622,7 +1623,7 @@ Possible values:

 Default value: 0

-## optimize_skip_unused_shards_rewrite_in {#optimize-skip-unused-shardslrewrite-in}
+## optimize_skip_unused_shards_rewrite_in {#optimize-skip-unused-shards-rewrite-in}

 Rewrite IN in query for remote shards to exclude values that does not belong to the shard (requires optimize_skip_unused_shards).

@ -1802,6 +1803,27 @@ Possible values:

 Default value: 0.

+## distributed_directory_monitor_split_batch_on_failure {#distributed_directory_monitor_split_batch_on_failure}
+
+Enables/disables splitting batches on failures.
+
+Sometimes sending particular batch to the remote shard may fail, because of some complex pipeline after (i.e. `MATERIALIZED VIEW` with `GROUP BY`) due to `Memory limit exceeded` or similar errors. In this case, retrying will not help (and this will stuck distributed sends for the table) but sending files from that batch one by one may succeed INSERT.
+
+So installing this setting to `1` will disable batching for such batches (i.e. temporary disables `distributed_directory_monitor_batch_inserts` for failed batches).
+
+Possible values:
+
+-   1 — Enabled.
+-   0 — Disabled.
+
+Default value: 0.
+
+!!! note "Note"
+    This setting also affects broken batches (that may appears because of abnormal server (machine) termination and no `fsync_after_insert`/`fsync_directories` for [Distributed](../../engines/table-engines/special/distributed.md) table engine).
+
+!!! warning "Warning"
+    You should not rely on automatic batch splitting, since this may hurt performance.
+
 ## os_thread_priority {#setting-os-thread-priority}

 Sets the priority ([nice](https://en.wikipedia.org/wiki/Nice_(Unix))) for threads that execute queries. The OS scheduler considers this priority when choosing the next thread to run on each available CPU core.
@ -2085,7 +2107,7 @@ Default value: 128.

 ## background_fetches_pool_size {#background_fetches_pool_size}

-Sets the number of threads performing background fetches for [replicated](../../engines/table-engines/mergetree-family/replication.md) tables. This setting is applied at the ClickHouse server start and can’t be changed in a user session. For production usage with frequent small insertions or slow ZooKeeper cluster is recomended to use default value.
+Sets the number of threads performing background fetches for [replicated](../../engines/table-engines/mergetree-family/replication.md) tables. This setting is applied at the ClickHouse server start and can’t be changed in a user session. For production usage with frequent small insertions or slow ZooKeeper cluster is recommended to use default value.

 Possible values:

@ -3079,4 +3101,82 @@ SELECT
 FROM fuse_tbl
 ```

-[Original article](https://clickhouse.tech/docs/en/operations/settings/settings/) <!-- hide -->
+## flatten_nested {#flatten-nested}
+
+Sets the data format of a [nested](../../sql-reference/data-types/nested-data-structures/nested.md) columns.
+
+Possible values:
+
+-   1 — Nested column is flattened to separate arrays.
+-   0 — Nested column stays a single array of tuples.
+
+Default value: `1`.
+
+**Usage**
+
+If the setting is set to `0`, it is possible to use an arbitrary level of nesting.
+
+**Examples**
+
+Query:
+
+``` sql
+SET flatten_nested = 1;
+CREATE TABLE t_nest (`n` Nested(a UInt32, b UInt32)) ENGINE = MergeTree ORDER BY tuple();
+
+SHOW CREATE TABLE t_nest;
+```
+
+Result:
+
+``` text
+┌─statement───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
+│ CREATE TABLE default.t_nest
+(
+    `n.a` Array(UInt32),
+    `n.b` Array(UInt32)
+)
+ENGINE = MergeTree
+ORDER BY tuple()
+SETTINGS index_granularity = 8192 │
+└─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
+```
+
+Query:
+
+``` sql
+SET flatten_nested = 0;
+
+CREATE TABLE t_nest (`n` Nested(a UInt32, b UInt32)) ENGINE = MergeTree ORDER BY tuple();
+
+SHOW CREATE TABLE t_nest;
+```
+
+Result:
+
+``` text
+┌─statement──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
+│ CREATE TABLE default.t_nest
+(
+    `n` Nested(a UInt32, b UInt32)
+)
+ENGINE = MergeTree
+ORDER BY tuple()
+SETTINGS index_granularity = 8192 │
+└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
+```
+
+## external_table_functions_use_nulls {#external-table-functions-use-nulls}
+
+Defines how [mysql](../../sql-reference/table-functions/mysql.md), [postgresql](../../sql-reference/table-functions/postgresql.md) and [odbc](../../sql-reference/table-functions/odbc.md)] table functions use Nullable columns.
+
+Possible values:
+
+-   0 — The table function explicitly uses Nullable columns.
+-   1 — The table function implicitly uses Nullable columns.
+
+Default value: `1`.
+
+**Usage**
+
+If the setting is set to `0`, the table function does not make Nullable columns and inserts default values instead of NULL. This is also applicable for NULL values inside arrays.
--- a/docs/en/operations/system-tables/data_skipping_indices.md
+++ b/docs/en/operations/system-tables/data_skipping_indices.md
@ -0,0 +1,39 @@
+# system.data_skipping_indices {#system-data-skipping-indices}
+
+Contains information about existing data skipping indices in all the tables.
+
+Columns:
+
+-   `database` ([String](../../sql-reference/data-types/string.md)) — Database name.
+-   `table` ([String](../../sql-reference/data-types/string.md)) — Table name.
+-   `name` ([String](../../sql-reference/data-types/string.md)) — Index name.
+-   `type` ([String](../../sql-reference/data-types/string.md)) — Index type.
+-   `expr` ([String](../../sql-reference/data-types/string.md)) — Expression used to calculate the index.
+-   `granularity` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Number of granules in the block.
+
+**Example**
+
+
+```sql
+SELECT * FROM system.data_skipping_indices LIMIT 2 FORMAT Vertical;
+```
+
+```text
+Row 1:
+──────
+database:    default
+table:       user_actions
+name:        clicks_idx
+type:        minmax
+expr:        clicks
+granularity: 1
+
+Row 2:
+──────
+database:    default
+table:       users
+name:        contacts_null_idx
+type:        minmax
+expr:        assumeNotNull(contacts_null)
+granularity: 1
+```
--- a/docs/en/operations/system-tables/processes.md
+++ b/docs/en/operations/system-tables/processes.md
@ -53,10 +53,8 @@ memory_usage:         0
 peak_memory_usage:    0
 query:                SELECT * from system.processes LIMIT 10 FORMAT Vertical;
 thread_ids:           [67]
-ProfileEvents.Names:  ['Query','SelectQuery','ReadCompressedBytes','CompressedReadBufferBlocks','CompressedReadBufferBytes','IOBufferAllocs','IOBufferAllocBytes','ContextLock','RWLockAcquiredReadLocks']
-ProfileEvents.Values: [1,1,36,1,10,1,89,16,1]
-Settings.Names:       ['use_uncompressed_cache','load_balancing','log_queries','max_memory_usage']
-Settings.Values:      ['0','in_order','1','10000000000']
+ProfileEvents:        {'Query':1,'SelectQuery':1,'ReadCompressedBytes':36,'CompressedReadBufferBlocks':1,'CompressedReadBufferBytes':10,'IOBufferAllocs':1,'IOBufferAllocBytes':89,'ContextLock':15,'RWLockAcquiredReadLocks':1}
+Settings:             {'background_pool_size':'32','load_balancing':'random','allow_suspicious_low_cardinality_types':'1','distributed_aggregation_memory_efficient':'1','skip_unavailable_shards':'1','log_queries':'1','max_bytes_before_external_group_by':'20000000000','max_bytes_before_external_sort':'20000000000','allow_introspection_functions':'1'}

 1 rows in set. Elapsed: 0.002 sec.
 ```
--- a/docs/en/operations/system-tables/query_log.md
+++ b/docs/en/operations/system-tables/query_log.md
@ -84,12 +84,10 @@ Columns:
 -   `forwarded_for` ([String](../../sql-reference/data-types/string.md)) — HTTP header `X-Forwarded-For` passed in the HTTP query.
 -   `quota_key` ([String](../../sql-reference/data-types/string.md)) — The `quota key` specified in the [quotas](../../operations/quotas.md) setting (see `keyed`).
 -   `revision` ([UInt32](../../sql-reference/data-types/int-uint.md)) — ClickHouse revision.
+-   `ProfileEvents` ([Map(String, UInt64)](../../sql-reference/data-types/array.md)) — ProfileEvents that measure different metrics. The description of them could be found in the table [system.events](../../operations/system-tables/events.md#system_tables-events)
+-   `Settings` ([Map(String, String)](../../sql-reference/data-types/array.md)) — Settings that were changed when the client ran the query. To enable logging changes to settings, set the `log_query_settings` parameter to 1.
 -   `log_comment` ([String](../../sql-reference/data-types/string.md)) — Log comment. It can be set to arbitrary string no longer than [max_query_size](../../operations/settings/settings.md#settings-max_query_size). An empty string if it is not defined.
 -   `thread_ids` ([Array(UInt64)](../../sql-reference/data-types/array.md)) — Thread ids that are participating in query execution.
-   `ProfileEvents.Names` ([Array(String)](../../sql-reference/data-types/array.md)) — Counters that measure different metrics. The description of them could be found in the table [system.events](../../operations/system-tables/events.md#system_tables-events)
-   `ProfileEvents.Values` ([Array(UInt64)](../../sql-reference/data-types/array.md)) — Values of metrics that are listed in the `ProfileEvents.Names` column.
-   `Settings.Names` ([Array(String)](../../sql-reference/data-types/array.md)) — Names of settings that were changed when the client ran the query. To enable logging changes to settings, set the `log_query_settings` parameter to 1.
-   `Settings.Values` ([Array(String)](../../sql-reference/data-types/array.md)) — Values of settings that are listed in the `Settings.Names` column.
 -   `used_aggregate_functions` ([Array(String)](../../sql-reference/data-types/array.md)) — Canonical names of `aggregate functions`, which were used during query execution.
 -   `used_aggregate_function_combinators` ([Array(String)](../../sql-reference/data-types/array.md)) — Canonical names of `aggregate functions combinators`, which were used during query execution.
 -   `used_database_engines` ([Array(String)](../../sql-reference/data-types/array.md)) — Canonical names of `database engines`, which were used during query execution.
@ -109,68 +107,49 @@ SELECT * FROM system.query_log WHERE type = 'QueryFinish' AND (query LIKE '%toDa
 ``` text
 Row 1:
 ──────
-type:                                QueryFinish
-event_date:                          2021-03-18
-event_time:                          2021-03-18 20:54:18
-event_time_microseconds:             2021-03-18 20:54:18.676686
-query_start_time:                    2021-03-18 20:54:18
-query_start_time_microseconds:       2021-03-18 20:54:18.673934
-query_duration_ms:                   2
-read_rows:                           100
-read_bytes:                          800
-written_rows:                        0
-written_bytes:                       0
-result_rows:                         2
-result_bytes:                        4858
-memory_usage:                        0
-current_database:                    default
-query:                               SELECT uniqArray([1, 1, 2]), SUBSTRING('Hello, world', 7, 5), flatten([[[BIT_AND(123)]], [[mod(3, 2)], [CAST('1' AS INTEGER)]]]), week(toDate('2000-12-05')), CAST(arrayJoin([NULL, NULL]) AS Nullable(TEXT)), avgOrDefaultIf(number, number % 2), sumOrNull(number), toTypeName(sumOrNull(number)), countIf(toDate('2000-12-05') + number as d, toDayOfYear(d) % 2) FROM numbers(100)
-normalized_query_hash:               17858008518552525706
-query_kind:                          Select
-databases:                           ['_table_function']
-tables:                              ['_table_function.numbers']
-columns:                             ['_table_function.numbers.number']
-exception_code:                      0
+type:                          QueryStart
+event_date:                    2020-09-11
+event_time:                    2020-09-11 10:08:17
+event_time_microseconds:       2020-09-11 10:08:17.063321
+query_start_time:              2020-09-11 10:08:17
+query_start_time_microseconds: 2020-09-11 10:08:17.063321
+query_duration_ms:             0
+read_rows:                     0
+read_bytes:                    0
+written_rows:                  0
+written_bytes:                 0
+result_rows:                   0
+result_bytes:                  0
+memory_usage:                  0
+current_database:              default
+query:                         INSERT INTO test1 VALUES
+exception_code:                0
 exception:
 stack_trace:
-is_initial_query:                    1
-user:                                default
-query_id:                            58f3d392-0fa0-4663-ae1d-29917a1a9c9c
-address:                             ::ffff:127.0.0.1
-port:                                37486
-initial_user:                        default
-initial_query_id:                    58f3d392-0fa0-4663-ae1d-29917a1a9c9c
-initial_address:                     ::ffff:127.0.0.1
-initial_port:                        37486
-interface:                           1
-os_user:                             sevirov
-client_hostname:                     clickhouse.ru-central1.internal
-client_name:                         ClickHouse
-client_revision:                     54447
-client_version_major:                21
-client_version_minor:                4
-client_version_patch:                1
-http_method:                         0
+is_initial_query:              1
+user:                          default
+query_id:                      50a320fd-85a8-49b8-8761-98a86bcbacef
+address:                       ::ffff:127.0.0.1
+port:                          33452
+initial_user:                  default
+initial_query_id:              50a320fd-85a8-49b8-8761-98a86bcbacef
+initial_address:               ::ffff:127.0.0.1
+initial_port:                  33452
+interface:                     1
+os_user:                       bharatnc
+client_hostname:               tower
+client_name:                   ClickHouse
+client_revision:               54437
+client_version_major:          20
+client_version_minor:          7
+client_version_patch:          2
+http_method:                   0
 http_user_agent:
-http_referer:
-forwarded_for:
 quota_key:
-revision:                            54449
-log_comment:
-thread_ids:                          [587,11939]
-ProfileEvents.Names:                 ['Query','SelectQuery','ReadCompressedBytes','CompressedReadBufferBlocks','CompressedReadBufferBytes','IOBufferAllocs','IOBufferAllocBytes','ArenaAllocChunks','ArenaAllocBytes','FunctionExecute','TableFunctionExecute','NetworkSendElapsedMicroseconds','SelectedRows','SelectedBytes','ContextLock','RWLockAcquiredReadLocks','RealTimeMicroseconds','UserTimeMicroseconds','SystemTimeMicroseconds','SoftPageFaults','OSCPUVirtualTimeMicroseconds','OSWriteBytes']
-ProfileEvents.Values:                [1,1,36,1,10,2,1048680,1,4096,36,1,110,100,800,77,1,3137,1476,1101,8,2577,8192]
-Settings.Names:                      ['load_balancing','max_memory_usage']
-Settings.Values:                     ['random','10000000000']
-used_aggregate_functions:            ['groupBitAnd','avg','sum','count','uniq']
-used_aggregate_function_combinators: ['OrDefault','If','OrNull','Array']
-used_database_engines:               []
-used_data_type_families:             ['String','Array','Int32','Nullable']
-used_dictionaries:                   []
-used_formats:                        []
-used_functions:                      ['toWeek','CAST','arrayFlatten','toTypeName','toDayOfYear','addDays','array','toDate','modulo','substring','plus']
-used_storages:                       []
-used_table_functions:                ['numbers']
+revision:                      54440
+thread_ids:                    []
+ProfileEvents:        {'Query':1,'SelectQuery':1,'ReadCompressedBytes':36,'CompressedReadBufferBlocks':1,'CompressedReadBufferBytes':10,'IOBufferAllocs':1,'IOBufferAllocBytes':89,'ContextLock':15,'RWLockAcquiredReadLocks':1}
+Settings:             {'background_pool_size':'32','load_balancing':'random','allow_suspicious_low_cardinality_types':'1','distributed_aggregation_memory_efficient':'1','skip_unavailable_shards':'1','log_queries':'1','max_bytes_before_external_group_by':'20000000000','max_bytes_before_external_sort':'20000000000','allow_introspection_functions':'1'}
 ```

 **See Also**
--- a/docs/en/operations/system-tables/query_thread_log.md
+++ b/docs/en/operations/system-tables/query_thread_log.md
@ -58,8 +58,7 @@ Columns:
 -   `http_user_agent` ([String](../../sql-reference/data-types/string.md)) — The `UserAgent` header passed in the HTTP request.
 -   `quota_key` ([String](../../sql-reference/data-types/string.md)) — The “quota key” specified in the [quotas](../../operations/quotas.md) setting (see `keyed`).
 -   `revision` ([UInt32](../../sql-reference/data-types/int-uint.md)) — ClickHouse revision.
-   `ProfileEvents.Names` ([Array(String)](../../sql-reference/data-types/array.md)) — Counters that measure different metrics for this thread. The description of them could be found in the table [system.events](#system_tables-events).
-   `ProfileEvents.Values` ([Array(UInt64)](../../sql-reference/data-types/array.md)) — Values of metrics for this thread that are listed in the `ProfileEvents.Names` column.
+-   `ProfileEvents` ([Map(String, UInt64)](../../sql-reference/data-types/array.md)) — ProfileEvents that measure different metrics for this thread. The description of them could be found in the table [system.events](#system_tables-events).

 **Example**

@ -107,8 +106,7 @@ http_method:                   0
 http_user_agent:
 quota_key:
 revision:                      54440
-ProfileEvents.Names:           ['Query','InsertQuery','FileOpen','WriteBufferFromFileDescriptorWrite','WriteBufferFromFileDescriptorWriteBytes','ReadCompressedBytes','CompressedReadBufferBlocks','CompressedReadBufferBytes','IOBufferAllocs','IOBufferAllocBytes','FunctionExecute','CreatedWriteBufferOrdinary','DiskWriteElapsedMicroseconds','NetworkReceiveElapsedMicroseconds','NetworkSendElapsedMicroseconds','InsertedRows','InsertedBytes','SelectedRows','SelectedBytes','MergeTreeDataWriterRows','MergeTreeDataWriterUncompressedBytes','MergeTreeDataWriterCompressedBytes','MergeTreeDataWriterBlocks','MergeTreeDataWriterBlocksAlreadySorted','ContextLock','RWLockAcquiredReadLocks','RealTimeMicroseconds','UserTimeMicroseconds','SoftPageFaults','OSCPUVirtualTimeMicroseconds','OSWriteBytes','OSReadChars','OSWriteChars']
-ProfileEvents.Values:          [1,1,11,11,591,148,3,71,29,6533808,1,11,72,18,47,1,12,1,12,1,12,189,1,1,10,2,70853,2748,49,2747,45056,422,1520]
+ProfileEvents:        {'Query':1,'SelectQuery':1,'ReadCompressedBytes':36,'CompressedReadBufferBlocks':1,'CompressedReadBufferBytes':10,'IOBufferAllocs':1,'IOBufferAllocBytes':89,'ContextLock':15,'RWLockAcquiredReadLocks':1}
 ```

 **See Also**
--- a/docs/en/operations/tips.md
+++ b/docs/en/operations/tips.md
@ -30,14 +30,6 @@ Do not disable overcommit. The value `cat /proc/sys/vm/overcommit_memory` should
 $ echo 0 | sudo tee /proc/sys/vm/overcommit_memory
 ```

-## Huge Pages {#huge-pages}
-
-Always disable transparent huge pages. It interferes with memory allocators, which leads to significant performance degradation.
-
-``` bash
-$ echo 'madvise' | sudo tee /sys/kernel/mm/transparent_hugepage/enabled
-```
-
 Use `perf top` to watch the time spent in the kernel for memory management.
 Permanent huge pages also do not need to be allocated.

@ -91,6 +83,15 @@ The Linux kernel prior to 3.2 had a multitude of problems with IPv6 implementati

 Use at least a 10 GB network, if possible. 1 Gb will also work, but it will be much worse for patching replicas with tens of terabytes of data, or for processing distributed queries with a large amount of intermediate data.

+## Huge Pages {#huge-pages}
+
+If you are using old Linux kernel, disable transparent huge pages. It interferes with memory allocators, which leads to significant performance degradation.
+On newer Linux kernels transparent huge pages are alright.
+
+``` bash
+$ echo 'madvise' | sudo tee /sys/kernel/mm/transparent_hugepage/enabled
+```
+
 ## Hypervisor configuration

 If you are using OpenStack, set
--- a/docs/en/sql-reference/aggregate-functions/reference/initializeAggregation.md
+++ b/docs/en/sql-reference/aggregate-functions/reference/initializeAggregation.md
@ -1,37 +0,0 @@
---
-toc_priority: 150
---
-
-## initializeAggregation {#initializeaggregation}
-
-Initializes aggregation for your input rows. It is intended for the functions with the suffix `State`.
-Use it for tests or to process columns of types `AggregateFunction` and `AggregationgMergeTree`.
-
-**Syntax**
-
-``` sql
-initializeAggregation (aggregate_function, column_1, column_2)
-```
-
-**Arguments**
-
-   `aggregate_function` — Name of the aggregation function. The state of this function — the creating one. [String](../../../sql-reference/data-types/string.md#string).
-   `column_n` — The column to translate it into the function as it's argument. [String](../../../sql-reference/data-types/string.md#string).
-
-**Returned value(s)**
-
-Returns the result of the aggregation for your input rows. The return type will be the same as the return type of function, that `initializeAgregation` takes as first argument.
-For example for functions with the suffix `State` the return type will be `AggregateFunction`.
-
-**Example**
-
-Query:
-
-```sql
-SELECT uniqMerge(state) FROM (SELECT initializeAggregation('uniqState', number % 3) AS state FROM system.numbers LIMIT 10000);
-```
-Result:
-
-┌─uniqMerge(state)─┐
-│                3 │
-└──────────────────┘
--- a/docs/en/sql-reference/data-types/array.md
+++ b/docs/en/sql-reference/data-types/array.md
@ -74,4 +74,26 @@ Received exception from server (version 1.1.54388):
 Code: 386. DB::Exception: Received from localhost:9000, 127.0.0.1. DB::Exception: There is no supertype for types UInt8, String because some of them are String/FixedString and some of them are not.
 ```

-[Original article](https://clickhouse.tech/docs/en/data_types/array/) <!--hide-->
+## Array Size {#array-size}
+
+It is possible to find the size of an array by using the `size0` subcolumn without reading the whole column. For multi-dimensional arrays you can use `sizeN-1`, where `N` is the wanted dimension.
+
+**Example**
+
+Query:
+
+```sql
+CREATE TABLE t_arr (`arr` Array(Array(Array(UInt32)))) ENGINE = MergeTree ORDER BY tuple();
+
+INSERT INTO t_arr VALUES ([[[12, 13, 0, 1],[12]]]);
+
+SELECT arr.size0, arr.size1, arr.size2 FROM t_arr;
+```
+
+Result:
+
+``` text
+┌─arr.size0─┬─arr.size1─┬─arr.size2─┐
+│         1 │ [2]       │ [[4,1]]   │
+└───────────┴───────────┴───────────┘
+```
--- a/docs/en/sql-reference/data-types/nested-data-structures/nested.md
+++ b/docs/en/sql-reference/data-types/nested-data-structures/nested.md
@ -34,7 +34,7 @@ CREATE TABLE test.visits

 This example declares the `Goals` nested data structure, which contains data about conversions (goals reached). Each row in the ‘visits’ table can correspond to zero or any number of conversions.

-Only a single nesting level is supported. Columns of nested structures containing arrays are equivalent to multidimensional arrays, so they have limited support (there is no support for storing these columns in tables with the MergeTree engine).
+When [flatten_nested](../../../operations/settings/settings.md#flatten-nested) is set to `0` (which is not by default), arbitrary levels of nesting are supported.

 In most cases, when working with a nested data structure, its columns are specified with column names separated by a dot. These columns make up an array of matching types. All the column arrays of a single nested data structure have the same length.

--- a/docs/en/sql-reference/data-types/nullable.md
+++ b/docs/en/sql-reference/data-types/nullable.md
@ -20,6 +20,33 @@ To store `Nullable` type values in a table column, ClickHouse uses a separate fi
 !!! info "Note"
    Using `Nullable` almost always negatively affects performance, keep this in mind when designing your databases.

+## Finding NULL {#finding-null}
+
+It is possible to find `NULL` values in a column by using `null` subcolumn without reading the whole column. It returns `1` if the corresponding value is `NULL` and `0` otherwise.
+
+**Example**
+
+Query:
+
+``` sql
+CREATE TABLE nullable (`n` Nullable(UInt32)) ENGINE = MergeTree ORDER BY tuple();
+
+INSERT INTO nullable VALUES (1) (NULL) (2) (NULL);
+
+SELECT n.null FROM nullable;
+```
+
+Result:
+
+``` text
+┌─n.null─┐
+│      0 │
+│      1 │
+│      0 │
+│      1 │
+└────────┘
+```
+
 ## Usage Example {#usage-example}

 ``` sql
--- a/docs/en/sql-reference/data-types/tuple.md
+++ b/docs/en/sql-reference/data-types/tuple.md
@ -47,4 +47,32 @@ SELECT tuple(1, NULL) AS x, toTypeName(x)
 └──────────┴─────────────────────────────────┘
 ```

+## Addressing Tuple Elements {#addressing-tuple-elements}
+
+It is possible to read elements of named tuples using indexes and names:
+
+``` sql
+CREATE TABLE named_tuples (`a` Tuple(s String, i Int64)) ENGINE = Memory;
+
+INSERT INTO named_tuples VALUES (('y', 10)), (('x',-10));
+
+SELECT a.s FROM named_tuples;
+
+SELECT a.2 FROM named_tuples;
+```
+
+Result:
+
+``` text
+┌─a.s─┐
+│ y   │
+│ x   │
+└─────┘
+
+┌─tupleElement(a, 2)─┐
+│                 10 │
+│                -10 │
+└────────────────────┘
+```
+
 [Original article](https://clickhouse.tech/docs/en/data_types/tuple/) <!--hide-->
--- a/docs/en/sql-reference/dictionaries/external-dictionaries/external-dicts-dict-sources.md
+++ b/docs/en/sql-reference/dictionaries/external-dictionaries/external-dicts-dict-sources.md
@ -486,6 +486,7 @@ Example of settings:
      <table>table_name</table>
      <where>id=10</where>
      <invalidate_query>SQL_QUERY</invalidate_query>
+      <fail_on_connection_loss>true</fail_on_connection_loss>
  </mysql>
 </source>
 ```
@ -503,6 +504,7 @@ SOURCE(MYSQL(
    table 'table_name'
    where 'id=10'
    invalidate_query 'SQL_QUERY'
+    fail_on_connection_loss 'true'
 ))
 ```

@ -527,6 +529,8 @@ Setting fields:

 -   `invalidate_query` – Query for checking the dictionary status. Optional parameter. Read more in the section [Updating dictionaries](../../../sql-reference/dictionaries/external-dictionaries/external-dicts-dict-lifetime.md).

+-   `fail_on_connection_loss` – The configuration parameter that controls behavior of the server on connection loss. If `true`, an exception is thrown immediately if the connection between client and server was lost. If `false`, the ClickHouse server retries to execute the query three times before throwing an exception. Note that retrying leads to increased response times. Default value: `false`.
+
 MySQL can be connected on a local host via sockets. To do this, set `host` and `socket`.

 Example of settings:
@ -542,6 +546,7 @@ Example of settings:
      <table>table_name</table>
      <where>id=10</where>
      <invalidate_query>SQL_QUERY</invalidate_query>
+      <fail_on_connection_loss>true</fail_on_connection_loss>
  </mysql>
 </source>
 ```
@ -558,6 +563,7 @@ SOURCE(MYSQL(
    table 'table_name'
    where 'id=10'
    invalidate_query 'SQL_QUERY'
+    fail_on_connection_loss 'true'
 ))
 ```

--- a/docs/en/sql-reference/functions/array-functions.md
+++ b/docs/en/sql-reference/functions/array-functions.md
@ -39,13 +39,44 @@ Accepts zero arguments and returns an empty array of the appropriate type.

 Accepts an empty array and returns a one-element array that is equal to the default value.

-## range(end), range(start, end \[, step\]) {#rangeend-rangestart-end-step}

-Returns an array of numbers from start to end-1 by step.
-If the argument `start` is not specified, defaults to 0.
-If the argument `step` is not specified, defaults to 1.
-It behaviors almost like pythonic `range`. But the difference is that all the arguments type must be `UInt` numbers.
-Just in case, an exception is thrown if arrays with a total length of more than 100,000,000 elements are created in a data block.
+## range(end), range(\[start, \] end \[, step\]) {#range}
+
+Returns an array of `UInt` numbers from `start` to `end - 1` by `step`.
+
+**Syntax**
+``` sql
+range([start, ] end [, step])
+```
+
+**Arguments**
+
+-   `start` — The first element of the array. Optional, required if `step` is used. Default value: 0. [UInt](../data-types/int-uint.md)
+-   `end` — The number before which the array is constructed. Required. [UInt](../data-types/int-uint.md)
+-   `step` — Determines the incremental step between each element in the array. Optional. Default value: 1. [UInt](../data-types/int-uint.md)
+
+**Returned value**
+
+-   Array of `UInt` numbers from `start` to `end - 1` by `step`.
+
+**Implementation details**
+
+-   All arguments must be positive values: `start`, `end`, `step` are `UInt` data types, as well as elements of the returned array.
+-   An exception is thrown if query results in arrays with a total length of more than 100,000,000 elements.
+
+
+**Examples**
+
+Query:
+``` sql
+SELECT range(5), range(1, 5), range(1, 5, 2);
+```
+Result:
+```txt
+┌─range(5)────┬─range(1, 5)─┬─range(1, 5, 2)─┐
+│ [0,1,2,3,4] │ [1,2,3,4]   │ [1,3]          │
+└─────────────┴─────────────┴────────────────┘
+```

 ## array(x1, …), operator \[x1, …\] {#arrayx1-operator-x1}

--- a/docs/en/sql-reference/functions/other-functions.md
+++ b/docs/en/sql-reference/functions/other-functions.md
@ -1424,6 +1424,78 @@ Result:
 └───────────┴────────┘
 ```

+## initializeAggregation {#initializeaggregation}
+
+Calculates result of aggregate function based on single value. It is intended to use this function to initialize aggregate functions with combinator [-State](../../sql-reference/aggregate-functions/combinators.md#agg-functions-combinator-state). You can create states of aggregate functions and insert them to columns of type [AggregateFunction](../../sql-reference/data-types/aggregatefunction.md#data-type-aggregatefunction) or use initialized aggregates as default values.
+
+**Syntax**
+
+``` sql
+initializeAggregation (aggregate_function, arg1, arg2, ..., argN)
+```
+
+**Arguments**
+
+-   `aggregate_function` — Name of the aggregation function to initialize. [String](../../sql-reference/data-types/string.md).
+-   `arg` — Arguments of aggregate function.
+
+**Returned value(s)**
+
+- Result of aggregation for every row passed to the function.
+
+The return type is the same as the return type of function, that `initializeAgregation` takes as first argument.
+
+**Example**
+
+Query:
+
+```sql
+SELECT uniqMerge(state) FROM (SELECT initializeAggregation('uniqState', number % 3) AS state FROM numbers(10000));
+```
+Result:
+
+```text
+┌─uniqMerge(state)─┐
+│                3 │
+└──────────────────┘
+```
+
+Query:
+
+```sql
+SELECT finalizeAggregation(state), toTypeName(state) FROM (SELECT initializeAggregation('sumState', number % 3) AS state FROM numbers(5));
+```
+Result:
+
+```text
+┌─finalizeAggregation(state)─┬─toTypeName(state)─────────────┐
+│                          0 │ AggregateFunction(sum, UInt8) │
+│                          1 │ AggregateFunction(sum, UInt8) │
+│                          2 │ AggregateFunction(sum, UInt8) │
+│                          0 │ AggregateFunction(sum, UInt8) │
+│                          1 │ AggregateFunction(sum, UInt8) │
+└────────────────────────────┴───────────────────────────────┘
+```
+
+Example with `AggregatingMergeTree` table engine and `AggregateFunction` column:
+
+```sql
+CREATE TABLE metrics
+(
+    key UInt64,
+    value AggregateFunction(sum, UInt64) DEFAULT initializeAggregation('sumState', toUInt64(0))
+)
+ENGINE = AggregatingMergeTree
+ORDER BY key
+```
+
+```sql
+INSERT INTO metrics VALUES (0, initializeAggregation('sumState', toUInt64(42)))
+```
+
+**See Also**
+-   [arrayReduce](../../sql-reference/functions/array-functions.md#arrayreduce)
+
 ## finalizeAggregation {#function-finalizeaggregation}

 Takes state of aggregate function. Returns result of aggregation (or finalized state when using[-State](../../sql-reference/aggregate-functions/combinators.md#agg-functions-combinator-state) combinator).
@ -1521,9 +1593,8 @@ Result:
 ```

 **See Also**
-
 -   [arrayReduce](../../sql-reference/functions/array-functions.md#arrayreduce)
-   [initializeAggregation](../../sql-reference/aggregate-functions/reference/initializeAggregation.md)
+-   [initializeAggregation](#initializeaggregation)

 ## runningAccumulate {#runningaccumulate}

--- a/docs/en/sql-reference/statements/system.md
+++ b/docs/en/sql-reference/statements/system.md
@ -119,7 +119,7 @@ For manage uncompressed data cache parameters use following server level setting
 ## DROP COMPILED EXPRESSION CACHE {#query_language-system-drop-compiled-expression-cache}

 Reset the compiled expression cache. Used in development of ClickHouse and performance tests.
-Complied expression cache used when query/user/profile enable option [compile](../../operations/settings/settings.md#compile)
+Compiled expression cache used when query/user/profile enable option [compile-expressions](../../operations/settings/settings.md#compile-expressions)

 ## FLUSH LOGS {#query_language-system-flush_logs}

--- a/docs/en/sql-reference/table-functions/mysql.md
+++ b/docs/en/sql-reference/table-functions/mysql.md
@ -39,6 +39,18 @@ Simple `WHERE` clauses such as `=, !=, >, >=, <, <=` are currently executed on t

 The rest of the conditions and the `LIMIT` sampling constraint are executed in ClickHouse only after the query to MySQL finishes.

+Supports multiple replicas that must be listed by `|`. For example:
+
+```sql
+SELECT name FROM mysql(`mysql{1|2|3}:3306`, 'mysql_database', 'mysql_table', 'user', 'password');
+```
+
+or
+
+```sql
+SELECT name FROM mysql(`mysql1:3306|mysql2:3306|mysql3:3306`, 'mysql_database', 'mysql_table', 'user', 'password');
+```
+
 **Returned Value**

 A table object with the same columns as the original MySQL table.
--- a/docs/en/sql-reference/table-functions/postgresql.md
+++ b/docs/en/sql-reference/table-functions/postgresql.md
@ -44,6 +44,18 @@ PostgreSQL Array types converts into ClickHouse arrays.
 !!! info "Note"
    Be careful, in PostgreSQL an array data type column like Integer[] may contain arrays of different dimensions in different rows, but in ClickHouse it is only allowed to have multidimensional arrays of the same dimension in all rows.
 	
+Supports multiple replicas that must be listed by `|`. For example:
+
+```sql
+SELECT name FROM postgresql(`postgres{1|2|3}:5432`, 'postgres_database', 'postgres_table', 'user', 'password');
+```
+
+or
+
+```sql
+SELECT name FROM postgresql(`postgres1:5431|postgres2:5432`, 'postgres_database', 'postgres_table', 'user', 'password');
+```
+
 Supports replicas priority for PostgreSQL dictionary source. The bigger the number in map, the less the priority. The highest priority is `0`.

 **Examples**
--- a/docs/ja/operations/settings/settings.md
+++ b/docs/ja/operations/settings/settings.md
@ -817,22 +817,6 @@ load_balancing = first_or_random
 のための一貫性を異なる部分に同じデータを分割)、このオプションにしているときだけサンプリングキーを設定します。
 レプリカラグは制御されません。

-## コンパイル {#compile}
-
-を編集ます。 既定では、0(無効)です。
-
-コンパイルは、クエリ処理パイプラインの一部にのみ使用されます。
-この部分のパイプラインのためのクエリを実行するアによる展開の短サイクルinlining集計機能。 複数の単純な集計関数を使用するクエリでは、最大のパフォーマンスの向上が見られます。 通常、性能は軽微であります。 非常に珍しい例で遅くなクエリを実行します。
-
-## min_count_to_compile {#min-count-to-compile}
-
-り方を潜在的に利用コチャンクのコードの実行前に作成する。 デフォルトでは3.
-For testing, the value can be set to 0: compilation runs synchronously and the query waits for the end of the compilation process before continuing execution. For all other cases, use values starting with 1. Compilation normally takes about 5-10 seconds.
-値が1以上の場合、コンパイルは別のスレッドで非同期に実行されます。 結果は、現在実行中のクエリを含め、準備が整うとすぐに使用されます。
-
-コンパイルされたコードは、クエリで使用される集計関数とGROUP BY句内のキーの種類のそれぞれの異なる組み合わせに必要です。
-The results of the compilation are saved in the build directory in the form of .so files. There is no restriction on the number of compilation results since they don't use very much space. Old results will be used after server restarts, except in the case of a server upgrade – in this case, the old results are deleted.
-
 ## output_format_json_quote_64bit_integers {#session_settings-output_format_json_quote_64bit_integers}

 値がtrueの場合、json\*Int64およびUInt64形式（ほとんどのJavaScript実装との互換性のため）を使用するときに整数が引用符で表示されます。
--- a/docs/ja/operations/system-tables.md
+++ b/docs/ja/operations/system-tables.md
@ -625,10 +625,8 @@ ClickHouseはこのテーブルを作成します。 [query_log](server-configur
 -   `quota_key` (String) — The “quota key” で指定される。 [クォータ](quotas.md) 設定(参照 `keyed`).
 -   `revision` (UInt32) — ClickHouse revision.
 -   `thread_numbers` (Array(UInt32)) — Number of threads that are participating in query execution.
-   `ProfileEvents.Names` (Array(String)) — Counters that measure different metrics. The description of them could be found in the table [システムイベント](#system_tables-events)
-   `ProfileEvents.Values` (Array(UInt64)) — Values of metrics that are listed in the `ProfileEvents.Names` 列。
-   `Settings.Names` (Array(String)) — Names of settings that were changed when the client ran the query. To enable logging changes to settings, set the `log_query_settings` パラメータは1。
-   `Settings.Values` (Array(String)) — Values of settings that are listed in the `Settings.Names` 列。
+-   `ProfileEvents` (Map(String, UInt64)) — ProfileEvents that measure different metrics. The description of them could be found in the table [システムイベント](#system_tables-events)
+-   `Settings` (Map(String, String)) — Settings  列。

 それぞれのクエリでは、一つまたは二つの行が `query_log` クエリのステータスに応じて、テーブル:

@ -698,8 +696,7 @@ ClickHouseはこのテーブルを作成します。 [query_thread_log](server-c
 -   `http_user_agent` (String) — The `UserAgent` HTTP要求で渡されるヘッダー。
 -   `quota_key` (String) — The “quota key” で指定される。 [クォータ](quotas.md) 設定(参照 `keyed`).
 -   `revision` (UInt32) — ClickHouse revision.
-   `ProfileEvents.Names` (Array(String)) — Counters that measure different metrics for this thread. The description of them could be found in the table [システムイベント](#system_tables-events)
-   `ProfileEvents.Values` (Array(UInt64)) — Values of metrics for this thread that are listed in the `ProfileEvents.Names` 列。
+-   `ProfileEvents` (Map(String, UInt64)) — ProfileEvents that measure different metrics for this thread. The description of them could be found in the table [システムイベント](#system_tables-events)

 既定では、ログは7.5秒間隔でテーブルに追加されます。 この間隔は [query_thread_log](server-configuration-parameters/settings.md#server_configuration_parameters-query-thread-log) サーバ設定(参照 `flush_interval_milliseconds` 変数）。 ログをメモリバッファからテーブルに強制的にフラッシュするには、 `SYSTEM FLUSH LOGS` クエリ。

--- a/docs/ru/engines/table-engines/integrations/ExternalDistributed.md
+++ b/docs/ru/engines/table-engines/integrations/ExternalDistributed.md
@ -0,0 +1,53 @@
+---
+toc_priority: 12
+toc_title: ExternalDistributed
+---
+
+# ExternalDistributed {#externaldistributed}
+
+Движок `ExternalDistributed` позволяет выполнять запросы `SELECT` для таблиц на удаленном сервере MySQL или PostgreSQL. Принимает в качестве аргумента табличные движки [MySQL](../../../engines/table-engines/integrations/mysql.md) или [PostgreSQL](../../../engines/table-engines/integrations/postgresql.md), поэтому возможно шардирование.
+
+## Создание таблицы {#creating-a-table}
+
+``` sql
+CREATE TABLE [IF NOT EXISTS] [db.]table_name [ON CLUSTER cluster]
+(
+    name1 [type1] [DEFAULT|MATERIALIZED|ALIAS expr1] [TTL expr1],
+    name2 [type2] [DEFAULT|MATERIALIZED|ALIAS expr2] [TTL expr2],
+    ...
+) ENGINE = ExternalDistributed('engine', 'host:port', 'database', 'table', 'user', 'password');
+```
+
+Смотрите подробное описание запроса [CREATE TABLE](../../../sql-reference/statements/create/table.md#create-table-query).
+
+Структура таблицы может отличаться от структуры исходной таблицы:
+
+-   Имена столбцов должны быть такими же, как в исходной таблице, но можно использовать только некоторые из этих столбцов и в любом порядке.
+-   Типы столбцов могут отличаться от типов в исходной таблице. ClickHouse пытается [привести](../../../sql-reference/functions/type-conversion-functions.md#type_conversion_function-cast) значения к типам данных ClickHouse.
+
+**Параметры движка**
+
+-   `engine` — табличный движок `MySQL` или `PostgreSQL`.
+-   `host:port` — адрес сервера MySQL или PostgreSQL.
+-   `database` — имя базы данных на сервере.
+-   `table` — имя таблицы.
+-   `user` — имя пользователя.
+-   `password` — пароль пользователя.
+
+## Особенности реализации {#implementation-details}
+	
+Поддерживает несколько реплик, которые должны быть перечислены через `|`, а шарды — через `,`. Например:
+
+```sql
+CREATE TABLE test_shards (id UInt32, name String, age UInt32, money UInt32) ENGINE = ExternalDistributed('MySQL', `mysql{1|2}:3306,mysql{3|4}:3306`, 'clickhouse', 'test_replicas', 'root', 'clickhouse');
+```
+
+При указании реплик для каждого из шардов при чтении выбирается одна из доступных реплик. Если соединиться не удалось, то выбирается следующая реплика, и так для всех реплик. Если попытка соединения не удалась для всех реплик, то сервер ClickHouse снова пытается соединиться с одной из реплик, перебирая их по кругу, и так несколько раз.
+
+Вы можете указать любое количество шардов и любое количество реплик для каждого шарда.
+
+**Смотрите также**
+
+-   [Табличный движок MySQL](../../../engines/table-engines/integrations/mysql.md)
+-   [Табличный движок PostgreSQL](../../../engines/table-engines/integrations/postgresql.md)
+-   [Табличный движок Distributed](../../../engines/table-engines/special/distributed.md)
--- a/docs/ru/engines/table-engines/integrations/mysql.md
+++ b/docs/ru/engines/table-engines/integrations/mysql.md
@ -20,11 +20,11 @@ CREATE TABLE [IF NOT EXISTS] [db.]table_name [ON CLUSTER cluster]

 Смотрите подробное описание запроса [CREATE TABLE](../../../sql-reference/statements/create/table.md#create-table-query).

-Структура таблицы может отличаться от исходной структуры таблицы MySQL:
+Структура таблицы может отличаться от структуры исходной таблицы MySQL:

-   Имена столбцов должны быть такими же, как в исходной таблице MySQL, но вы можете использовать только некоторые из этих столбцов и в любом порядке.
-   Типы столбцов могут отличаться от типов в исходной таблице MySQL. ClickHouse пытается [приводить](../../../sql-reference/functions/type-conversion-functions.md#type_conversion_function-cast) значения к типам данных ClickHouse.
-   Настройка `external_table_functions_use_nulls` определяет как обрабатывать Nullable столбцы. По умолчанию 1, если 0 - табличная функция не будет делать nullable столбцы и будет вместо null выставлять значения по умолчанию для скалярного типа. Это также применимо для null значений внутри массивов.
+-   Имена столбцов должны быть такими же, как в исходной таблице MySQL, но можно использовать только некоторые из этих столбцов и в любом порядке.
+-   Типы столбцов могут отличаться от типов в исходной таблице MySQL. ClickHouse пытается [привести](../../../engines/database-engines/mysql.md#data_types-support) значения к типам данных ClickHouse.
+-   Настройка [external_table_functions_use_nulls](../../../operations/settings/settings.md#external-table-functions-use-nulls) определяет как обрабатывать Nullable столбцы. Значение по умолчанию: 1. Если значение 0, то табличная функция не делает Nullable столбцы, а вместо NULL выставляет значения по умолчанию для скалярного типа. Это также применимо для значений NULL внутри массивов.

 **Параметры движка**

@ -50,6 +50,12 @@ CREATE TABLE [IF NOT EXISTS] [db.]table_name [ON CLUSTER cluster]

 Остальные условия и ограничение выборки `LIMIT` будут выполнены в ClickHouse только после выполнения запроса к MySQL.

+Поддерживает несколько реплик, которые должны быть перечислены через `|`. Например:
+
+```sql
+CREATE TABLE test_replicas (id UInt32, name String, age UInt32, money UInt32) ENGINE = MySQL(`mysql{2|3|4}:3306`, 'clickhouse', 'test_replicas', 'root', 'clickhouse');
+```
+
 ## Пример использования {#primer-ispolzovaniia}

 Таблица в MySQL:
--- a/docs/ru/engines/table-engines/integrations/odbc.md
+++ b/docs/ru/engines/table-engines/integrations/odbc.md
@ -29,7 +29,7 @@ ENGINE = ODBC(connection_settings, external_database, external_table)

 -   Имена столбцов должны быть такими же, как в исходной таблице, но вы можете использовать только некоторые из этих столбцов и в любом порядке.
 -   Типы столбцов могут отличаться от типов аналогичных столбцов в исходной таблице. ClickHouse пытается [приводить](../../../engines/table-engines/integrations/odbc.md#type_conversion_function-cast) значения к типам данных ClickHouse.
-   Настройка `external_table_functions_use_nulls` определяет как обрабатывать Nullable столбцы. По умолчанию 1, если 0 - табличная функция не будет делать nullable столбцы и будет вместо null выставлять значения по умолчанию для скалярного типа. Это также применимо для null значений внутри массивов.
+-   Настройка [external_table_functions_use_nulls](../../../operations/settings/settings.md#external-table-functions-use-nulls) определяет как обрабатывать Nullable столбцы. Значение по умолчанию: 1. Если значение 0, то табличная функция не делает Nullable столбцы, а вместо NULL выставляет значения по умолчанию для скалярного типа. Это также применимо для значений NULL внутри массивов.

 **Параметры движка**

--- a/docs/ru/engines/table-engines/integrations/postgresql.md
+++ b/docs/ru/engines/table-engines/integrations/postgresql.md
@ -20,19 +20,19 @@ CREATE TABLE [IF NOT EXISTS] [db.]table_name [ON CLUSTER cluster]

 Смотрите подробное описание запроса [CREATE TABLE](../../../sql-reference/statements/create/table.md#create-table-query).

-Структура таблицы может отличаться от исходной структуры таблицы PostgreSQL:
+Структура таблицы может отличаться от структуры исходной таблицы PostgreSQL:

-   Имена столбцов должны быть такими же, как в исходной таблице PostgreSQL, но вы можете использовать только некоторые из этих столбцов и в любом порядке.
-   Типы столбцов могут отличаться от типов в исходной таблице PostgreSQL. ClickHouse пытается [приводить](../../../sql-reference/functions/type-conversion-functions.md#type_conversion_function-cast) values to the ClickHouse data types.
-   Настройка `external_table_functions_use_nulls` определяет как обрабатывать Nullable столбцы. По умолчанию 1, если 0 - табличная функция не будет делать nullable столбцы и будет вместо null выставлять значения по умолчанию для скалярного типа. Это также применимо для null значений внутри массивов.
+-   Имена столбцов должны быть такими же, как в исходной таблице PostgreSQL, но можно использовать только некоторые из этих столбцов и в любом порядке.
+-   Типы столбцов могут отличаться от типов в исходной таблице PostgreSQL. ClickHouse пытается [привести](../../../engines/database-engines/postgresql.md#data_types-support) значения к типам данных ClickHouse.
+-   Настройка [external_table_functions_use_nulls](../../../operations/settings/settings.md#external-table-functions-use-nulls) определяет как обрабатывать Nullable столбцы. Значение по умолчанию: 1. Если значение 0, то табличная функция не делает Nullable столбцы, а вместо NULL выставляет значения по умолчанию для скалярного типа. Это также применимо для значений NULL внутри массивов.

 **Параметры движка**

 -   `host:port` — адрес сервера PostgreSQL.
-   `database` — Имя базы данных на сервере PostgreSQL.
-   `table` — Имя таблицы.
-   `user` — Имя пользователя PostgreSQL.
-   `password` — Пароль пользователя PostgreSQL.
+-   `database` — имя базы данных на сервере PostgreSQL.
+-   `table` — имя таблицы.
+-   `user` — имя пользователя PostgreSQL.
+-   `password` — пароль пользователя PostgreSQL.
 -   `schema` — имя схемы, если не используется схема по умолчанию. Необязательный аргумент. 

 ## Особенности реализации {#implementation-details}
@ -50,6 +50,12 @@ PostgreSQL массивы конвертируются в массивы ClickHo
 !!! info "Внимание"
    Будьте внимательны, в PostgreSQL массивы, созданные как `type_name[]`, являются многомерными и могут содержать в себе разное количество измерений в разных строках одной таблицы. Внутри ClickHouse допустимы только многомерные массивы с одинаковым кол-вом измерений во всех строках таблицы.
 	
+Поддерживает несколько реплик, которые должны быть перечислены через `|`. Например:
+
+```sql
+CREATE TABLE test_replicas (id UInt32, name String) ENGINE = PostgreSQL(`postgres{2|3|4}:5432`, 'clickhouse', 'test_replicas', 'postgres', 'mysecretpassword');
+```
+
 При использовании словаря PostgreSQL поддерживается приоритет реплик. Чем больше номер реплики, тем ниже ее приоритет. Наивысший приоритет у реплики с номером `0`.  

 В примере ниже реплика `example01-1` имеет более высокий приоритет:
--- a/docs/ru/operations/settings/settings.md
+++ b/docs/ru/operations/settings/settings.md
@ -1181,22 +1181,22 @@ load_balancing = round_robin
 !!! warning "Предупреждение"
    Параллельное выполнение запроса может привести к неверному результату, если в запросе есть объединение или подзапросы и при этом таблицы не удовлетворяют определенным требованиям. Подробности смотрите в разделе [Распределенные подзапросы и max_parallel_replicas](../../sql-reference/operators/in.md#max_parallel_replica-subqueries).

+## compile_expressions {#compile-expressions}

-## compile {#compile}
+Включает или выключает компиляцию часто используемых функций и операторов. Компиляция производится в нативный код платформы с помощью LLVM во время выполнения.

-Включить компиляцию запросов. По умолчанию - 0 (выключено).
+Возможные значения:

-Компиляция предусмотрена только для части конвейера обработки запроса - для первой стадии агрегации (GROUP BY).
-В случае, если эта часть конвейера была скомпилирована, запрос может работать быстрее, за счёт разворачивания коротких циклов и инлайнинга вызовов агрегатных функций. Максимальный прирост производительности (до четырёх раз в редких случаях) достигается на запросах с несколькими простыми агрегатными функциями. Как правило, прирост производительности незначителен. В очень редких случаях возможно замедление выполнения запроса.
+- 0 — компиляция выключена.
+- 1 — компиляция включена.

-## min_count_to_compile {#min-count-to-compile}
+Значение по умолчанию: `1`.

-После скольких раз, когда скомпилированный кусок кода мог пригодиться, выполнить его компиляцию. По умолчанию - 3.
-Для тестирования можно установить значение 0: компиляция выполняется синхронно, и запрос ожидает окончания процесса компиляции перед продолжением выполнения. Во всех остальных случаях используйте значения, начинающиеся с 1. Как правило, компиляция занимает по времени около 5-10 секунд.
-В случае, если значение равно 1 или больше, компиляция выполняется асинхронно, в отдельном потоке. При готовности результата, он сразу же будет использован, в том числе, уже выполняющимися в данный момент запросами.
+## min_count_to_compile_expression {#min-count-to-compile-expression}

-Скомпилированный код требуется для каждого разного сочетания используемых в запросе агрегатных функций и вида ключей в GROUP BY.
-Результаты компиляции сохраняются в директории build в виде .so файлов. Количество результатов компиляции не ограничено, так как они не занимают много места. При перезапуске сервера, старые результаты будут использованы, за исключением случая обновления сервера - тогда старые результаты удаляются.
+Минимальное количество выполнений одного и того же выражения до его компиляции.
+
+Значение по умолчанию: `3`.

 ## input_format_skip_unknown_fields {#input-format-skip-unknown-fields}

@ -2957,4 +2957,83 @@ SELECT
 FROM fuse_tbl
 ```

-[Оригинальная статья](https://clickhouse.tech/docs/ru/operations/settings/settings/) <!--hide-->
+## flatten_nested {#flatten-nested}
+
+Устанавливает формат данных у [вложенных](../../sql-reference/data-types/nested-data-structures/nested.md) столбцов.
+
+Возможные значения:
+
+-   1 — вложенный столбец преобразуется к отдельным массивам.
+-   0 — вложенный столбец преобразуется к массиву кортежей.
+
+Значение по умолчанию: `1`.
+
+**Использование**
+
+Если установлено значение `0`, можно использовать любой уровень вложенности.
+
+**Примеры**
+
+Запрос:
+
+``` sql
+SET flatten_nested = 1;
+
+CREATE TABLE t_nest (`n` Nested(a UInt32, b UInt32)) ENGINE = MergeTree ORDER BY tuple();
+
+SHOW CREATE TABLE t_nest;
+```
+
+Результат:
+
+``` text
+┌─statement───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
+│ CREATE TABLE default.t_nest
+(
+    `n.a` Array(UInt32),
+    `n.b` Array(UInt32)
+)
+ENGINE = MergeTree
+ORDER BY tuple()
+SETTINGS index_granularity = 8192 │
+└─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
+```
+
+Запрос:
+
+``` sql
+SET flatten_nested = 0;
+
+CREATE TABLE t_nest (`n` Nested(a UInt32, b UInt32)) ENGINE = MergeTree ORDER BY tuple();
+
+SHOW CREATE TABLE t_nest;
+```
+
+Результат:
+
+``` text
+┌─statement──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
+│ CREATE TABLE default.t_nest
+(
+    `n` Nested(a UInt32, b UInt32)
+)
+ENGINE = MergeTree
+ORDER BY tuple()
+SETTINGS index_granularity = 8192 │
+└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
+```
+
+## external_table_functions_use_nulls {#external-table-functions-use-nulls}
+
+Определяет, как табличные функции [mysql](../../sql-reference/table-functions/mysql.md), [postgresql](../../sql-reference/table-functions/postgresql.md) и [odbc](../../sql-reference/table-functions/odbc.md)] используют Nullable столбцы.
+
+Возможные значения:
+
+-   0 — табличная функция явно использует Nullable столбцы.
+-   1 — табличная функция неявно использует Nullable столбцы.
+
+Значение по умолчанию: `1`.
+
+**Использование**
+
+Если установлено значение `0`, то табличная функция не делает Nullable столбцы, а вместо NULL выставляет значения по умолчанию для скалярного типа. Это также применимо для значений NULL внутри массивов.
--- a/docs/ru/operations/system-tables/query_log.md
+++ b/docs/ru/operations/system-tables/query_log.md
@ -84,12 +84,10 @@ ClickHouse не удаляет данные из таблица автомати
 -   `forwarded_for` ([String](../../sql-reference/data-types/string.md)) — HTTP заголовок `X-Forwarded-For`.
 -   `quota_key` ([String](../../sql-reference/data-types/string.md)) — `ключ квоты` из настроек [квот](quotas.md) (см. `keyed`).
 -   `revision` ([UInt32](../../sql-reference/data-types/int-uint.md)) — ревизия ClickHouse.
+-   `ProfileEvents` ([Map(String, UInt64)](../../sql-reference/data-types/array.md)) — счетчики для изменения различных метрик. Описание метрик можно получить из таблицы [system.events](#system_tables-events)(#system_tables-events
+-   `Settings` ([Map(String, String)](../../sql-reference/data-types/array.md)) — имена настроек, которые меняются, когда клиент выполняет запрос. Чтобы разрешить логирование изменений настроек, установите параметр `log_query_settings` равным 1.
 -   `log_comment` ([String](../../sql-reference/data-types/string.md)) — комментарий к записи в логе. Представляет собой произвольную строку, длина которой должна быть не больше, чем [max_query_size](../../operations/settings/settings.md#settings-max_query_size). Если нет комментария, то пустая строка.
 -   `thread_ids` ([Array(UInt64)](../../sql-reference/data-types/array.md)) — идентификаторы потоков, участвующих в обработке запросов.
-   `ProfileEvents.Names` ([Array(String)](../../sql-reference/data-types/array.md)) — счетчики для изменения различных метрик. Описание метрик можно получить из таблицы [system.events](#system_tables-events)(#system_tables-events
-   `ProfileEvents.Values` ([Array(UInt64)](../../sql-reference/data-types/array.md)) — метрики, перечисленные в столбце `ProfileEvents.Names`.
-   `Settings.Names` ([Array(String)](../../sql-reference/data-types/array.md)) — имена настроек, которые меняются, когда клиент выполняет запрос. Чтобы разрешить логирование изменений настроек, установите параметр `log_query_settings` равным 1.
-   `Settings.Values` ([Array(String)](../../sql-reference/data-types/array.md)) — значения настроек, которые перечислены в столбце `Settings.Names`.
 -   `used_aggregate_functions` ([Array(String)](../../sql-reference/data-types/array.md)) — канонические имена `агрегатных функций`, использованных при выполнении запроса.
 -   `used_aggregate_function_combinators` ([Array(String)](../../sql-reference/data-types/array.md)) — канонические имена `комбинаторов агрегатных функций`, использованных при выполнении запроса.
 -   `used_database_engines` ([Array(String)](../../sql-reference/data-types/array.md)) — канонические имена `движков баз данных`, использованных при выполнении запроса.
@ -109,68 +107,49 @@ SELECT * FROM system.query_log WHERE type = 'QueryFinish' AND (query LIKE '%toDa
 ``` text
 Row 1:
 ──────
-type:                                QueryFinish
-event_date:                          2021-03-18
-event_time:                          2021-03-18 20:54:18
-event_time_microseconds:             2021-03-18 20:54:18.676686
-query_start_time:                    2021-03-18 20:54:18
-query_start_time_microseconds:       2021-03-18 20:54:18.673934
-query_duration_ms:                   2
-read_rows:                           100
-read_bytes:                          800
-written_rows:                        0
-written_bytes:                       0
-result_rows:                         2
-result_bytes:                        4858
-memory_usage:                        0
-current_database:                    default
-query:                               SELECT uniqArray([1, 1, 2]), SUBSTRING('Hello, world', 7, 5), flatten([[[BIT_AND(123)]], [[mod(3, 2)], [CAST('1' AS INTEGER)]]]), week(toDate('2000-12-05')), CAST(arrayJoin([NULL, NULL]) AS Nullable(TEXT)), avgOrDefaultIf(number, number % 2), sumOrNull(number), toTypeName(sumOrNull(number)), countIf(toDate('2000-12-05') + number as d, toDayOfYear(d) % 2) FROM numbers(100)
-normalized_query_hash:               17858008518552525706
-query_kind:                          Select
-databases:                           ['_table_function']
-tables:                              ['_table_function.numbers']
-columns:                             ['_table_function.numbers.number']
-exception_code:                      0
+type:                          QueryStart
+event_date:                    2020-09-11
+event_time:                    2020-09-11 10:08:17
+event_time_microseconds:       2020-09-11 10:08:17.063321
+query_start_time:              2020-09-11 10:08:17
+query_start_time_microseconds: 2020-09-11 10:08:17.063321
+query_duration_ms:             0
+read_rows:                     0
+read_bytes:                    0
+written_rows:                  0
+written_bytes:                 0
+result_rows:                   0
+result_bytes:                  0
+memory_usage:                  0
+current_database:              default
+query:                         INSERT INTO test1 VALUES
+exception_code:                0
 exception:
 stack_trace:
-is_initial_query:                    1
-user:                                default
-query_id:                            58f3d392-0fa0-4663-ae1d-29917a1a9c9c
-address:                             ::ffff:127.0.0.1
-port:                                37486
-initial_user:                        default
-initial_query_id:                    58f3d392-0fa0-4663-ae1d-29917a1a9c9c
-initial_address:                     ::ffff:127.0.0.1
-initial_port:                        37486
-interface:                           1
-os_user:                             sevirov
-client_hostname:                     clickhouse.ru-central1.internal
-client_name:                         ClickHouse
-client_revision:                     54447
-client_version_major:                21
-client_version_minor:                4
-client_version_patch:                1
-http_method:                         0
+is_initial_query:              1
+user:                          default
+query_id:                      50a320fd-85a8-49b8-8761-98a86bcbacef
+address:                       ::ffff:127.0.0.1
+port:                          33452
+initial_user:                  default
+initial_query_id:              50a320fd-85a8-49b8-8761-98a86bcbacef
+initial_address:               ::ffff:127.0.0.1
+initial_port:                  33452
+interface:                     1
+os_user:                       bharatnc
+client_hostname:               tower
+client_name:                   ClickHouse
+client_revision:               54437
+client_version_major:          20
+client_version_minor:          7
+client_version_patch:          2
+http_method:                   0
 http_user_agent:
-http_referer:
-forwarded_for:
 quota_key:
-revision:                            54449
-log_comment:
-thread_ids:                          [587,11939]
-ProfileEvents.Names:                 ['Query','SelectQuery','ReadCompressedBytes','CompressedReadBufferBlocks','CompressedReadBufferBytes','IOBufferAllocs','IOBufferAllocBytes','ArenaAllocChunks','ArenaAllocBytes','FunctionExecute','TableFunctionExecute','NetworkSendElapsedMicroseconds','SelectedRows','SelectedBytes','ContextLock','RWLockAcquiredReadLocks','RealTimeMicroseconds','UserTimeMicroseconds','SystemTimeMicroseconds','SoftPageFaults','OSCPUVirtualTimeMicroseconds','OSWriteBytes']
-ProfileEvents.Values:                [1,1,36,1,10,2,1048680,1,4096,36,1,110,100,800,77,1,3137,1476,1101,8,2577,8192]
-Settings.Names:                      ['load_balancing','max_memory_usage']
-Settings.Values:                     ['random','10000000000']
-used_aggregate_functions:            ['groupBitAnd','avg','sum','count','uniq']
-used_aggregate_function_combinators: ['OrDefault','If','OrNull','Array']
-used_database_engines:               []
-used_data_type_families:             ['String','Array','Int32','Nullable']
-used_dictionaries:                   []
-used_formats:                        []
-used_functions:                      ['toWeek','CAST','arrayFlatten','toTypeName','toDayOfYear','addDays','array','toDate','modulo','substring','plus']
-used_storages:                       []
-used_table_functions:                ['numbers']
+revision:                      54440
+thread_ids:                    []
+ProfileEvents:        {'Query':1,'SelectQuery':1,'ReadCompressedBytes':36,'CompressedReadBufferBlocks':1,'CompressedReadBufferBytes':10,'IOBufferAllocs':1,'IOBufferAllocBytes':89,'ContextLock':15,'RWLockAcquiredReadLocks':1}
+Settings:             {'background_pool_size':'32','load_balancing':'random','allow_suspicious_low_cardinality_types':'1','distributed_aggregation_memory_efficient':'1','skip_unavailable_shards':'1','log_queries':'1','max_bytes_before_external_group_by':'20000000000','max_bytes_before_external_sort':'20000000000','allow_introspection_functions':'1'}
 ```

 **Смотрите также**
--- a/docs/ru/operations/system-tables/query_thread_log.md
+++ b/docs/ru/operations/system-tables/query_thread_log.md
@ -57,8 +57,7 @@ ClickHouse не удаляет данные из таблицы автомати
 -   `http_user_agent` ([String](../../sql-reference/data-types/string.md)) — HTTP заголовок `UserAgent`.
 -   `quota_key` ([String](../../sql-reference/data-types/string.md)) — «ключ квоты» из настроек [квот](quotas.md) (см. `keyed`).
 -   `revision` ([UInt32](../../sql-reference/data-types/int-uint.md)) — ревизия ClickHouse.
-   `ProfileEvents.Names` ([Array(String)](../../sql-reference/data-types/array.md)) — счетчики для изменения различных метрик для данного потока. Описание метрик можно получить из таблицы [system.events](#system_tables-events).
-   `ProfileEvents.Values` ([Array(UInt64)](../../sql-reference/data-types/array.md)) — метрики для данного потока, перечисленные в столбце `ProfileEvents.Names`.
+-   `ProfileEvents` ([Map(String, UInt64)](../../sql-reference/data-types/array.md)) — счетчики для изменения различных метрик для данного потока. Описание метрик можно получить из таблицы [system.events](#system_tables-events).

 **Пример**

@ -106,8 +105,7 @@ http_method:                   0
 http_user_agent:
 quota_key:
 revision:                      54440
-ProfileEvents.Names:           ['Query','InsertQuery','FileOpen','WriteBufferFromFileDescriptorWrite','WriteBufferFromFileDescriptorWriteBytes','ReadCompressedBytes','CompressedReadBufferBlocks','CompressedReadBufferBytes','IOBufferAllocs','IOBufferAllocBytes','FunctionExecute','CreatedWriteBufferOrdinary','DiskWriteElapsedMicroseconds','NetworkReceiveElapsedMicroseconds','NetworkSendElapsedMicroseconds','InsertedRows','InsertedBytes','SelectedRows','SelectedBytes','MergeTreeDataWriterRows','MergeTreeDataWriterUncompressedBytes','MergeTreeDataWriterCompressedBytes','MergeTreeDataWriterBlocks','MergeTreeDataWriterBlocksAlreadySorted','ContextLock','RWLockAcquiredReadLocks','RealTimeMicroseconds','UserTimeMicroseconds','SoftPageFaults','OSCPUVirtualTimeMicroseconds','OSWriteBytes','OSReadChars','OSWriteChars']
-ProfileEvents.Values:          [1,1,11,11,591,148,3,71,29,6533808,1,11,72,18,47,1,12,1,12,1,12,189,1,1,10,2,70853,2748,49,2747,45056,422,1520]
+ProfileEvents:        {'Query':1,'SelectQuery':1,'ReadCompressedBytes':36,'CompressedReadBufferBlocks':1,'CompressedReadBufferBytes':10,'IOBufferAllocs':1,'IOBufferAllocBytes':89,'ContextLock':15,'RWLockAcquiredReadLocks':1}
 ```

 **Смотрите также**
--- a/docs/ru/sql-reference/aggregate-functions/reference/initializeAggregation.md
+++ b/docs/ru/sql-reference/aggregate-functions/reference/initializeAggregation.md
@ -1,40 +0,0 @@
---
-toc_priority: 150
---
-
-## initializeAggregation {#initializeaggregation}
-
-Инициализирует агрегацию для введеных строчек. Предназначена для функций с суффиксом `State`.
-Поможет вам проводить тесты или работать со столбцами типов: `AggregateFunction` и `AggregationgMergeTree`.
-
-**Синтаксис**
-
-``` sql
-initializeAggregation (aggregate_function, column_1, column_2)
-```
-
-**Аргументы**
-
-   `aggregate_function` — название функции агрегации, состояние которой нужно создать. [String](../../../sql-reference/data-types/string.md#string).
-   `column_n` — столбец, который передается в функцию агрегации как аргумент. [String](../../../sql-reference/data-types/string.md#string).
-
-**Возвращаемое значение**
-
-Возвращает результат агрегации введенной информации. Тип возвращаемого значения такой же, как и для функции, которая становится первым аргументом для `initializeAgregation`.
-
-Пример:
-
-Возвращаемый тип функций с суффиксом `State`  — `AggregateFunction`.
-
-**Пример**
-
-Запрос:
-
-```sql
-SELECT uniqMerge(state) FROM (SELECT initializeAggregation('uniqState', number % 3) AS state FROM system.numbers LIMIT 10000);
-```
-Результат:
-
-┌─uniqMerge(state)─┐
-│                3 │
-└──────────────────┘
--- a/docs/ru/sql-reference/data-types/array.md
+++ b/docs/ru/sql-reference/data-types/array.md
@ -5,11 +5,9 @@ toc_title: Array(T)

 # Array(T) {#data-type-array}

-Массив из элементов типа `T`.
+Массив из элементов типа `T`. `T` может любым, в том числе массивом. Таким образом поддерживаются многомерные массивы.

-`T` может любым, в том числе, массивом. Таким образом поддержаны многомерные массивы.
-
-## Создание массива {#sozdanie-massiva}
+## Создание массива {#creating-an-array}

 Массив можно создать с помощью функции:

@ -45,7 +43,7 @@ SELECT [1, 2] AS x, toTypeName(x)
 └───────┴────────────────────┘
 ```

-## Особенности работы с типами данных {#osobennosti-raboty-s-tipami-dannykh}
+## Особенности работы с типами данных {#working-with-data-types}

 Максимальный размер массива ограничен одним миллионом элементов.

@ -76,3 +74,26 @@ Received exception from server (version 1.1.54388):
 Code: 386. DB::Exception: Received from localhost:9000, 127.0.0.1. DB::Exception: There is no supertype for types UInt8, String because some of them are String/FixedString and some of them are not.
 ```

+## Размер массива {#array-size}
+
+Узнать размер массива можно с помощью подстолбца `size0` без чтения всего столбца. Для многомерных массивов можно использовать подстолбец `sizeN-1`, где `N` — требуемое измерение.
+
+**Пример**
+
+Запрос:
+
+```sql
+CREATE TABLE t_arr (`arr` Array(Array(Array(UInt32)))) ENGINE = MergeTree ORDER BY tuple();
+
+INSERT INTO t_arr VALUES ([[[12, 13, 0, 1],[12]]]);
+
+SELECT arr.size0, arr.size1, arr.size2 FROM t_arr;
+```
+
+Результат:
+
+``` text
+┌─arr.size0─┬─arr.size1─┬─arr.size2─┐
+│         1 │ [2]       │ [[4,1]]   │
+└───────────┴───────────┴───────────┘
+```
--- a/docs/ru/sql-reference/data-types/nested-data-structures/nested.md
+++ b/docs/ru/sql-reference/data-types/nested-data-structures/nested.md
@ -29,7 +29,7 @@ CREATE TABLE test.visits

 В этом примере объявлена вложенная структура данных `Goals`, содержащая данные о достижении целей. Каждой строке таблицы visits может соответствовать от нуля до произвольного количества достижений целей.

-Поддерживается только один уровень вложенности. Столбцы вложенных структур, содержащие массивы, эквивалентны многомерным массивам, поэтому их поддержка ограничена (не поддерживается хранение таких столбцов в таблицах с движком семейства MergeTree).
+Если настройка [flatten_nested](../../../operations/settings/settings.md#flatten-nested) установлена в значение `0` (что не является значением по умолчанию), поддерживаются любые уровни вложенности.

 В большинстве случаев, при работе с вложенной структурой данных, указываются отдельные её столбцы. Для этого, имена столбцов указываются через точку. Эти столбцы представляют собой массивы соответствующих типов. Все столбцы-массивы одной вложенной структуры данных имеют одинаковые длины.

--- a/docs/ru/sql-reference/data-types/nullable.md
+++ b/docs/ru/sql-reference/data-types/nullable.md
@ -13,7 +13,7 @@ toc_title: Nullable

 `NULL` — значение по умолчанию для типа `Nullable`, если в конфигурации сервера ClickHouse не указано иное.

-## Особенности хранения {#osobennosti-khraneniia}
+## Особенности хранения {#storage-features}

 Для хранения значения типа `Nullable` ClickHouse использует:

@ -27,7 +27,34 @@ toc_title: Nullable
 !!! info "Info"
    Почти всегда использование `Nullable` снижает производительность, учитывайте это при проектировании своих баз.

-## Пример использования {#primer-ispolzovaniia}
+## Поиск NULL {#finding-null}
+
+Найти в столбце значения `NULL` можно с помощью подстолбца `null`, при этом весь столбец считывать не требуется. Подстолбец содержит `1`, если соответствующее значение равно `NULL`, и `0` если не равно.
+
+**Пример**
+
+Запрос: 
+
+``` sql
+CREATE TABLE nullable (`n` Nullable(UInt32)) ENGINE = MergeTree ORDER BY tuple();
+
+INSERT INTO nullable VALUES (1) (NULL) (2) (NULL);
+
+SELECT n.null FROM nullable;
+```
+
+Результат:
+
+``` text
+┌─n.null─┐
+│      0 │
+│      1 │
+│      0 │
+│      1 │
+└────────┘
+```
+
+## Пример использования {#usage-example}

 ``` sql
 CREATE TABLE t_null(x Int8, y Nullable(Int8)) ENGINE TinyLog
@ -47,4 +74,3 @@ SELECT x + y from t_null
 │          5 │
 └────────────┘
 ```
-
--- a/docs/ru/sql-reference/data-types/tuple.md
+++ b/docs/ru/sql-reference/data-types/tuple.md
@ -47,3 +47,30 @@ SELECT tuple(1,NULL) AS x, toTypeName(x)
 └──────────┴─────────────────────────────────┘
 ```

+## Адресация элементов кортежа {#addressing-tuple-elements}
+
+К элементам кортежа можно обращаться по индексу и по имени:
+
+``` sql
+CREATE TABLE named_tuples (`a` Tuple(s String, i Int64)) ENGINE = Memory;
+
+INSERT INTO named_tuples VALUES (('y', 10)), (('x',-10));
+
+SELECT a.s FROM named_tuples;
+
+SELECT a.2 FROM named_tuples;
+```
+
+Результат:
+
+``` text
+┌─a.s─┐
+│ y   │
+│ x   │
+└─────┘
+
+┌─tupleElement(a, 2)─┐
+│                 10 │
+│                -10 │
+└────────────────────┘
+```
--- a/docs/ru/sql-reference/dictionaries/external-dictionaries/external-dicts-dict-sources.md
+++ b/docs/ru/sql-reference/dictionaries/external-dictionaries/external-dicts-dict-sources.md
@ -486,6 +486,7 @@ LIFETIME(MIN 300 MAX 360)
      <table>table_name</table>
      <where>id=10</where>
      <invalidate_query>SQL_QUERY</invalidate_query>
+      <fail_on_connection_loss>true</fail_on_connection_loss>
  </mysql>
 </source>
 ```
@ -503,6 +504,7 @@ SOURCE(MYSQL(
    table 'table_name'
    where 'id=10'
    invalidate_query 'SQL_QUERY'
+    fail_on_connection_loss 'true'
 ))
 ```

@ -527,6 +529,8 @@ SOURCE(MYSQL(

 -   `invalidate_query` — запрос для проверки статуса словаря. Необязательный параметр. Читайте подробнее в разделе [Обновление словарей](external-dicts-dict-lifetime.md).

+-   `fail_on_connection_loss` – параметр конфигурации, контролирующий поведение сервера при потере соединения. Если значение `true`, то исключение генерируется сразу же, если соединение между клиентом и сервером было потеряно. Если значение `false`, то сервер повторно попытается выполнить запрос три раза прежде чем сгенерировать исключение. Имейте в виду, что повторные попытки могут увеличить время выполнения запроса. Значение по умолчанию: `false`.
+
 MySQL можно подключить на локальном хосте через сокеты, для этого необходимо задать `host` и `socket`.

 Пример настройки:
@ -542,6 +546,7 @@ MySQL можно подключить на локальном хосте чер
      <table>table_name</table>
      <where>id=10</where>
      <invalidate_query>SQL_QUERY</invalidate_query>
+      <fail_on_connection_loss>true</fail_on_connection_loss>
  </mysql>
 </source>
 ```
@ -558,6 +563,7 @@ SOURCE(MYSQL(
    table 'table_name'
    where 'id=10'
    invalidate_query 'SQL_QUERY'
+    fail_on_connection_loss 'true'
 ))
 ```

--- a/docs/ru/sql-reference/functions/array-functions.md
+++ b/docs/ru/sql-reference/functions/array-functions.md
@ -39,10 +39,49 @@ toc_title: "Массивы"

 Принимает пустой массив и возвращает массив из одного элемента, равного значению по умолчанию.

-## range(N) {#rangen}

-Возвращает массив чисел от 0 до N-1.
-На всякий случай, если на блок данных, создаются массивы суммарной длины больше 100 000 000 элементов, то кидается исключение.
+## range(end), range(\[start, \] end \[, step\]) {#range}
+
+Возвращает массив чисел от `start` до `end - 1` с шагом `step`.
+
+**Синтаксис**
+
+``` sql
+range([start, ] end [, step])
+```
+
+**Аргументы**
+
+-   `start` — начало диапазона. Обязательно, когда указан `step`. По умолчанию равно `0`. Тип: [UInt](../data-types/int-uint.md)
+-   `end` — конец диапазона. Обязательный аргумент. Должен быть больше, чем `start`. Тип: [UInt](../data-types/int-uint.md)
+-   `step` — шаг обхода. Необязательный аргумент. По умолчанию равен `1`. Тип: [UInt](../data-types/int-uint.md)
+
+
+**Возвращаемые значения**
+
+-   массив `UInt` чисел от `start` до `end - 1` с шагом `step`
+
+
+**Особенности реализации**
+
+-   Не поддерживаются отрицательные значения аргументов: `start`, `end`, `step` имеют тип `UInt`.
+
+-   Если в результате запроса создаются массивы суммарной длиной больше 100 000 000 элементов, то генерируется исключение.
+
+
+**Примеры**
+
+Запрос:
+``` sql
+SELECT range(5), range(1, 5), range(1, 5, 2);
+```
+Ответ:
+```txt
+┌─range(5)────┬─range(1, 5)─┬─range(1, 5, 2)─┐
+│ [0,1,2,3,4] │ [1,2,3,4]   │ [1,3]          │
+└─────────────┴─────────────┴────────────────┘
+```
+

 ## array(x1, …), оператор \[x1, …\] {#arrayx1-operator-x1}

--- a/docs/ru/sql-reference/functions/other-functions.md
+++ b/docs/ru/sql-reference/functions/other-functions.md
@ -1371,6 +1371,79 @@ SELECT formatReadableSize(filesystemCapacity()) AS "Capacity", toTypeName(filesy
 └───────────┴────────┘
 ```

+## initializeAggregation {#initializeaggregation}
+
+Вычисляет результат агрегатной функции для каждой строки. Предназначена для инициализации агрегатных функций с комбинатором [-State](../../sql-reference/aggregate-functions/combinators.md#state). Может быть полезна для создания состояний агрегатных функций для последующей их вставки в столбцы типа [AggregateFunction](../../sql-reference/data-types/aggregatefunction.md#data-type-aggregatefunction) или использования в качестве значений по-умолчанию.
+
+**Синтаксис**
+
+``` sql
+initializeAggregation (aggregate_function, arg1, arg2, ..., argN)
+```
+
+**Аргументы**
+
+-   `aggregate_function` — название агрегатной функции, состояние которой нужно создать. [String](../../sql-reference/data-types/string.md#string).
+-   `arg` — аргументы, которые передаются в агрегатную функцию.
+
+**Возвращаемое значение**
+
+- В каждой строке результат агрегатной функции, примененной к аргументам из этой строки.
+
+Тип возвращаемого значения такой же, как и у функции, переданной первым аргументом.
+
+
+**Пример**
+
+Запрос:
+
+```sql
+SELECT uniqMerge(state) FROM (SELECT initializeAggregation('uniqState', number % 3) AS state FROM numbers(10000));
+```
+Результат:
+
+```text
+┌─uniqMerge(state)─┐
+│                3 │
+└──────────────────┘
+```
+
+Запрос:
+
+```sql
+SELECT finalizeAggregation(state), toTypeName(state) FROM (SELECT initializeAggregation('sumState', number % 3) AS state FROM numbers(5));
+```
+Результат:
+
+```text
+┌─finalizeAggregation(state)─┬─toTypeName(state)─────────────┐
+│                          0 │ AggregateFunction(sum, UInt8) │
+│                          1 │ AggregateFunction(sum, UInt8) │
+│                          2 │ AggregateFunction(sum, UInt8) │
+│                          0 │ AggregateFunction(sum, UInt8) │
+│                          1 │ AggregateFunction(sum, UInt8) │
+└────────────────────────────┴───────────────────────────────┘
+```
+
+Пример с движком таблиц `AggregatingMergeTree` и столбцом типа `AggregateFunction`:
+
+```sql
+CREATE TABLE metrics
+(
+    key UInt64,
+    value AggregateFunction(sum, UInt64) DEFAULT initializeAggregation('sumState', toUInt64(0))
+)
+ENGINE = AggregatingMergeTree
+ORDER BY key
+```
+
+```sql
+INSERT INTO metrics VALUES (0, initializeAggregation('sumState', toUInt64(42)))
+```
+
+**Смотрите также**
+-   [arrayReduce](../../sql-reference/functions/array-functions.md#arrayreduce)
+
 ## finalizeAggregation {#function-finalizeaggregation}

 Принимает состояние агрегатной функции. Возвращает результат агрегирования (или конечное состояние при использовании комбинатора [-State](../../sql-reference/aggregate-functions/combinators.md#state)).
@ -1470,7 +1543,7 @@ FROM numbers(10);
 **Смотрите также**

 -   [arrayReduce](../../sql-reference/functions/array-functions.md#arrayreduce)
-   [initializeAggregation](../../sql-reference/aggregate-functions/reference/initializeAggregation.md)
+-   [initializeAggregation](#initializeaggregation)

 ## runningAccumulate {#runningaccumulate}

--- a/docs/ru/sql-reference/statements/system.md
+++ b/docs/ru/sql-reference/statements/system.md
@ -115,7 +115,7 @@ SYSTEM DROP REPLICA 'replica_name' FROM ZKPATH '/path/to/table/in/zk';

 ## DROP COMPILED EXPRESSION CACHE {#query_language-system-drop-compiled-expression-cache}
 Сбрасывает кеш скомпилированных выражений. Используется при разработке ClickHouse и тестах производительности.
-Компилированные выражения используются когда включена настройка уровня запрос/пользователь/профиль [compile](../../operations/settings/settings.md#compile)
+Cкомпилированные выражения используются когда включена настройка уровня запрос/пользователь/профиль [compile-expressions](../../operations/settings/settings.md#compile-expressions)

 ## FLUSH LOGS {#query_language-system-flush_logs}

--- a/docs/ru/sql-reference/table-functions/mysql.md
+++ b/docs/ru/sql-reference/table-functions/mysql.md
@ -38,6 +38,18 @@ mysql('host:port', 'database', 'table', 'user', 'password'[, replace_query, 'on_

 Остальные условия и ограничение выборки `LIMIT` будут выполнены в ClickHouse только после выполнения запроса к MySQL.

+Поддерживает несколько реплик, которые должны быть перечислены через `|`. Например:
+
+```sql
+SELECT name FROM mysql(`mysql{1|2|3}:3306`, 'mysql_database', 'mysql_table', 'user', 'password');
+```
+
+или
+
+```sql
+SELECT name FROM mysql(`mysql1:3306|mysql2:3306|mysql3:3306`, 'mysql_database', 'mysql_table', 'user', 'password');
+```
+
 **Возвращаемое значение**

 Объект таблицы с теми же столбцами, что и в исходной таблице MySQL.
--- a/docs/ru/sql-reference/table-functions/postgresql.md
+++ b/docs/ru/sql-reference/table-functions/postgresql.md
@ -44,6 +44,18 @@ PostgreSQL массивы конвертируются в массивы ClickHo
 !!! info "Примечание"
    Будьте внимательны, в PostgreSQL массивы, созданные как `type_name[]`, являются многомерными и могут содержать в себе разное количество измерений в разных строках одной таблицы. Внутри ClickHouse допустипы только многомерные массивы с одинаковым кол-вом измерений во всех строках таблицы.
 	
+Поддерживает несколько реплик, которые должны быть перечислены через `|`. Например:
+
+```sql
+SELECT name FROM postgresql(`postgres{1|2|3}:5432`, 'postgres_database', 'postgres_table', 'user', 'password');
+```
+
+или
+
+```sql
+SELECT name FROM postgresql(`postgres1:5431|postgres2:5432`, 'postgres_database', 'postgres_table', 'user', 'password');
+```
+
 При использовании словаря PostgreSQL поддерживается приоритет реплик. Чем больше номер реплики, тем ниже ее приоритет. Наивысший приоритет у реплики с номером `0`.    

 **Примеры**
--- a/docs/tools/README.md
+++ b/docs/tools/README.md
@ -47,6 +47,13 @@ When all prerequisites are installed, running `build.py` without args (there are

 The easiest way to see the result is to use `--livereload=8888` argument of build.py. Alternatively, you can manually launch a HTTP server to serve the docs, for example by running `cd ClickHouse/docs/build && python3 -m http.server 8888`. Then go to http://localhost:8888 in browser. Feel free to use any other port instead of 8888.

+## How to change code highlighting? {#how-to-change-code-hl}
+
+ClickHouse does not use mkdocs `highlightjs` feature. It uses modified pygments styles instead.
+If you want to change code highlighting, edit the `website/css/highlight.css` file.
+Currently, an [eighties](https://github.com/idleberg/base16-pygments/blob/master/css/base16-eighties.dark.css) theme
+is used.
+
 ## How to subscribe on documentation changes? {#how-to-subscribe-on-documentation-changes}

 At the moment there’s no easy way to do just that, but you can consider:
--- a/docs/tools/build.py
+++ b/docs/tools/build.py
@ -87,6 +87,7 @@ def build_for_lang(lang, args):
        website_url = 'https://clickhouse.tech'
        site_name = site_names.get(lang, site_names['en']) % ''
        site_name = site_name.replace('  ', ' ')
+
        raw_config = dict(
            site_name=site_name,
            site_url=f'{website_url}/docs/{lang}/',
--- a/docs/zh/engines/table-engines/special/set.md
+++ b/docs/zh/engines/table-engines/special/set.md
@ -1,4 +1,4 @@
-# 设置 {#set}
+# 集合 {#set}

 始终存在于 RAM 中的数据集。它适用于IN运算符的右侧（请参见 «IN运算符» 部分）。

--- a/docs/zh/operations/settings/settings.md
+++ b/docs/zh/operations/settings/settings.md
@ -817,21 +817,22 @@ load_balancing = first_or_random
 为了保持一致性（以获取相同数据拆分的不同部分），此选项仅在设置了采样键时有效。
 副本滞后不受控制。

-## 编译 {#compile}
+## compile_expressions {#compile-expressions}

-启用查询的编译。 默认情况下，0（禁用）。
+啟用或禁用在運行時使用 LLVM 將常用的簡單函數和運算符編譯為本機代碼。

-编译仅用于查询处理管道的一部分：用于聚合的第一阶段（GROUP BY）。
-如果编译了管道的这一部分，则由于部署周期较短和内联聚合函数调用，查询可能运行得更快。 对于具有多个简单聚合函数的查询，可以看到最大的性能改进（在极少数情况下可快四倍）。 通常，性能增益是微不足道的。 在极少数情况下，它可能会减慢查询执行速度。
+可能的值：

-## min_count_to_compile {#min-count-to-compile}
+- 0 — 禁用。
+- 1 — 啟用。

-在运行编译之前可能使用已编译代码块的次数。 默认情况下，3。
-For testing, the value can be set to 0: compilation runs synchronously and the query waits for the end of the compilation process before continuing execution. For all other cases, use values starting with 1. Compilation normally takes about 5-10 seconds.
-如果该值为1或更大，则编译在单独的线程中异步进行。 结果将在准备就绪后立即使用，包括当前正在运行的查询。
+默認值：`1`。

-对于查询中使用的聚合函数的每个不同组合以及GROUP BY子句中的键类型，都需要编译代码。
-The results of the compilation are saved in the build directory in the form of .so files. There is no restriction on the number of compilation results since they don't use very much space. Old results will be used after server restarts, except in the case of a server upgrade – in this case, the old results are deleted.
+## min_count_to_compile_expression {#min-count-to-compile-expression}
+
+在編譯之前執行相同表達式的最小計數。
+
+默認值：`3`。

 ## output_format_json_quote_64bit_integers {#session_settings-output_format_json_quote_64bit_integers}

--- a/docs/zh/operations/system-tables/query_log.md
+++ b/docs/zh/operations/system-tables/query_log.md
@ -81,9 +81,9 @@ ClickHouse不会自动从表中删除数据。更多详情请看 [introduction](
 -   `http_user_agent` ([String](../../sql-reference/data-types/string.md)) — The `UserAgent` The UserAgent header passed in the HTTP request。
 -   `quota_key` ([String](../../sql-reference/data-types/string.md)) — 在[quotas](../../operations/quotas.md) 配置里设置的“quota key” （见 `keyed`).
 -   `revision` ([UInt32](../../sql-reference/data-types/int-uint.md)) — ClickHouse revision.
-   `thread_numbers` ([Array(UInt32)](../../sql-reference/data-types/array.md)) — 参与查询的线程数.
-   `ProfileEvents.Names` ([Array（String)](../../sql-reference/data-types/array.md)) — 衡量不同指标的计数器。 可以在[system.events](../../operations/system-tables/events.md#system_tables-events)中找到它们的描述。
-   `ProfileEvents.Values` ([Array(UInt64)](../../sql-reference/data-types/array.md)) — `ProfileEvents.Names` 列中列出的指标的值。
+-   `ProfileEvents` ([Map(String, UInt64))](../../sql-reference/data-types/array.md)) — Counters that measure different metrics. The description of them could be found in the table [系统。活动](../../operations/system-tables/events.md#system_tables-events)
+-   `Settings` ([Map(String, String)](../../sql-reference/data-types/array.md)) — Names of settings that were changed when the client ran the query. To enable logging changes to settings, set the `log_query_settings` 参数为1。
+-   `thread_ids` ([Array(UInt64)](../../sql-reference/data-types/array.md)) — 参与查询的线程数.
 -   `Settings.Names` ([Array（String)](../../sql-reference/data-types/array.md)) — 客户端运行查询时更改的设置的名称。 要启用对设置的日志记录更改，请将log_query_settings参数设置为1。
 -   `Settings.Values` ([Array（String)](../../sql-reference/data-types/array.md)) — `Settings.Names` 列中列出的设置的值。
 **示例**
@ -133,10 +133,8 @@ http_user_agent:
 quota_key:
 revision:             54434
 thread_ids:           []
-ProfileEvents.Names:  []
-ProfileEvents.Values: []
-Settings.Names:       ['use_uncompressed_cache','load_balancing','log_queries','max_memory_usage']
-Settings.Values:      ['0','random','1','10000000000']
+ProfileEvents:        {'Query':1,'SelectQuery':1,'ReadCompressedBytes':36,'CompressedReadBufferBlocks':1,'CompressedReadBufferBytes':10,'IOBufferAllocs':1,'IOBufferAllocBytes':89,'ContextLock':15,'RWLockAcquiredReadLocks':1}
+Settings:             {'background_pool_size':'32','load_balancing':'random','allow_suspicious_low_cardinality_types':'1','distributed_aggregation_memory_efficient':'1','skip_unavailable_shards':'1','log_queries':'1','max_bytes_before_external_group_by':'20000000000','max_bytes_before_external_sort':'20000000000','allow_introspection_functions':'1'}
 ```

 **另请参阅**
--- a/docs/zh/operations/system-tables/query_thread_log.md
+++ b/docs/zh/operations/system-tables/query_thread_log.md
@ -61,8 +61,7 @@ ClickHouse不会自动从表中删除数据。 看 [导言](../../operations/sys
 -   `http_user_agent` ([字符串](../../sql-reference/data-types/string.md)) — The `UserAgent` http请求中传递的标头。
 -   `quota_key` ([字符串](../../sql-reference/data-types/string.md)) — The “quota key” 在指定 [配额](../../operations/quotas.md) 设置（见 `keyed`).
 -   `revision` ([UInt32](../../sql-reference/data-types/int-uint.md)) — ClickHouse revision.
-   `ProfileEvents.Names` ([数组（字符串)](../../sql-reference/data-types/array.md)) — Counters that measure different metrics for this thread. The description of them could be found in the table [系统。活动](#system_tables-events).
-   `ProfileEvents.Values` ([数组(UInt64)](../../sql-reference/data-types/array.md)) — Values of metrics for this thread that are listed in the `ProfileEvents.Names` 列。
+-   `ProfileEvents` ([数组（字符串, UInt64)](../../sql-reference/data-types/array.md)) — Counters that measure different metrics for this thread. The description of them could be found in the table [系统。活动](#system_tables-events).

 **示例**

@ -108,8 +107,7 @@ http_method:          0
 http_user_agent:
 quota_key:
 revision:             54434
-ProfileEvents.Names:  ['ContextLock','RealTimeMicroseconds','UserTimeMicroseconds','OSCPUWaitMicroseconds','OSCPUVirtualTimeMicroseconds']
-ProfileEvents.Values: [1,97,81,5,81]
+ProfileEvents:        {'Query':1,'SelectQuery':1,'ReadCompressedBytes':36,'CompressedReadBufferBlocks':1,'CompressedReadBufferBytes':10,'IOBufferAllocs':1,'IOBufferAllocBytes':89,'ContextLock':15,'RWLockAcquiredReadLocks':1}
 ...
 ```

--- a/docs/zh/sql-reference/statements/system.md
+++ b/docs/zh/sql-reference/statements/system.md
@ -95,7 +95,7 @@ SYSTEM DROP REPLICA 'replica_name' FROM ZKPATH '/path/to/table/in/zk';
 ## DROP COMPILED EXPRESSION CACHE {#query_language-system-drop-compiled-expression-cache}

 重置已编译的表达式缓存。用于ClickHouse开发和性能测试。
-当 `query/user/profile` 启用配置项 [compile](../../operations/settings/settings.md#compile)时，编译的表达式缓存开启。
+当 `query/user/profile` 启用配置项 [compile-expressions](../../operations/settings/settings.md#compile-expressions)时，编译的表达式缓存开启。

 ## FLUSH LOGS {#query_language-system-flush_logs}

--- a/docs/zh/sql-reference/table-functions/postgresql.md
+++ b/docs/zh/sql-reference/table-functions/postgresql.md
@ -0,0 +1,120 @@
+---
+toc_priority: 42
+toc_title: postgresql
+---
+
+# postgresql {#postgresql}
+
+允许对存储在远程 PostgreSQL 服务器上的数据进行 `SELECT` 和 `INSERT` 查询.
+
+**语法**
+
+``` sql
+postgresql('host:port', 'database', 'table', 'user', 'password'[, `schema`])
+```
+
+**参数**
+
+-   `host:port` — PostgreSQL 服务器地址.
+-   `database` — 远程数据库名称.
+-   `table` — 远程表名称.
+-   `user` — PostgreSQL 用户.
+-   `password` — 用户密码.
+-   `schema` — 非默认的表结构. 可选.
+
+**返回值**
+
+一个表对象，其列数与原 PostgreSQL 表的列数相同。
+
+!!! info "Note"
+    在`INSERT`查询中，为了区分表函数`postgresql(..)`和表名以及表的列名列表，你必须使用关键字`FUNCTION`或`TABLE FUNCTION`。请看下面的例子。
+
+## 实施细节 {#implementation-details}
+
+`SELECT`查询在 PostgreSQL 上以 `COPY (SELECT ...) TO STDOUT` 的方式在只读的 PostgreSQL 事务中运行，每次在`SELECT`查询后提交。
+
+简单的`WHERE`子句，如`=`、`！=`、`>`、`>=`、`<`、`<=`和`IN`，在PostgreSQL服务器上执行。
+
+所有的连接、聚合、排序，`IN [ 数组 ]`条件和`LIMIT`采样约束只有在对PostgreSQL的查询结束后才会在ClickHouse中执行。
+
+PostgreSQL 上的`INSERT`查询以`COPY "table_name" (field1, field2, ... fieldN) FROM STDIN`的方式在 PostgreSQL 事务中运行，每次`INSERT`语句后自动提交。
+
+PostgreSQL 数组类型将转换为 ClickHouse 数组。
+
+!!! info "Note"
+    要小心，在 PostgreSQL 中，像 Integer[] 这样的数组数据类型列可以在不同的行中包含不同维度的数组，但在 ClickHouse 中，只允许在所有的行中有相同维度的多维数组。
+
+支持设置 PostgreSQL 字典源中 Replicas 的优先级。地图中的数字越大，优先级就越低。`0`代表最高的优先级。
+
+**示例**
+
+PostgreSQL 中的表:
+
+``` text
+postgres=# CREATE TABLE "public"."test" (
+"int_id" SERIAL,
+"int_nullable" INT NULL DEFAULT NULL,
+"float" FLOAT NOT NULL,
+"str" VARCHAR(100) NOT NULL DEFAULT '',
+"float_nullable" FLOAT NULL DEFAULT NULL,
+PRIMARY KEY (int_id));
+
+CREATE TABLE
+
+postgres=# INSERT INTO test (int_id, str, "float") VALUES (1,'test',2);
+INSERT 0 1
+
+postgresql> SELECT * FROM test;
+  int_id | int_nullable | float | str  | float_nullable
+ --------+--------------+-------+------+----------------
+       1 |              |     2 | test |
+(1 row)
+```
+
+从 ClickHouse 检索数据:
+
+```sql
+SELECT * FROM postgresql('localhost:5432', 'test', 'test', 'postgresql_user', 'password') WHERE str IN ('test');
+```
+
+``` text
+┌─int_id─┬─int_nullable─┬─float─┬─str──┬─float_nullable─┐
+│      1 │         ᴺᵁᴸᴸ │     2 │ test │           ᴺᵁᴸᴸ │
+└────────┴──────────────┴───────┴──────┴────────────────┘
+```
+
+插入数据:
+
+```sql
+INSERT INTO TABLE FUNCTION postgresql('localhost:5432', 'test', 'test', 'postgrsql_user', 'password') (int_id, float) VALUES (2, 3);
+SELECT * FROM postgresql('localhost:5432', 'test', 'test', 'postgresql_user', 'password');
+```
+
+``` text
+┌─int_id─┬─int_nullable─┬─float─┬─str──┬─float_nullable─┐
+│      1 │         ᴺᵁᴸᴸ │     2 │ test │           ᴺᵁᴸᴸ │
+│      2 │         ᴺᵁᴸᴸ │     3 │      │           ᴺᵁᴸᴸ │
+└────────┴──────────────┴───────┴──────┴────────────────┘
+```
+
+使用非默认的表结构:
+
+```text
+postgres=# CREATE SCHEMA "nice.schema";
+
+postgres=# CREATE TABLE "nice.schema"."nice.table" (a integer);
+
+postgres=# INSERT INTO "nice.schema"."nice.table" SELECT i FROM generate_series(0, 99) as t(i)
+```
+
+```sql
+CREATE TABLE pg_table_schema_with_dots (a UInt32)
+        ENGINE PostgreSQL('localhost:5432', 'clickhouse', 'nice.table', 'postgrsql_user', 'password', 'nice.schema');
+```
+
+**另请参阅**
+
+-   [PostgreSQL 表引擎](../../engines/table-engines/integrations/postgresql.md)
+-   [使用 PostgreSQL 作为外部字典的来源](../../sql-reference/dictionaries/external-dictionaries/external-dicts-dict-sources.md#dicts-external_dicts_dict_sources-postgresql)
+
+[原始文章](https://clickhouse.tech/docs/en/sql-reference/table-functions/postgresql/) <!--hide-->
--- a/programs/client/Client.cpp
+++ b/programs/client/Client.cpp
@ -577,7 +577,18 @@ private:
            }

            if (!history_file.empty() && !fs::exists(history_file))
-                FS::createFile(history_file);
+            {
+                /// Avoid TOCTOU issue.
+                try
+                {
+                    FS::createFile(history_file);
+                }
+                catch (const ErrnoException & e)
+                {
+                    if (e.getErrno() != EEXIST)
+                        throw;
+                }
+            }

            LineReader::Patterns query_extenders = {"\\"};
            LineReader::Patterns query_delimiters = {";", "\\G"};
@ -1369,9 +1380,19 @@ private:
                have_error = true;
            }

+            const auto * exception = server_exception ? server_exception.get() : client_exception.get();
+            // Sometimes you may get TOO_DEEP_RECURSION from the server,
+            // and TOO_DEEP_RECURSION should not fail the fuzzer check.
+            if (have_error && exception->code() == ErrorCodes::TOO_DEEP_RECURSION)
+            {
+                have_error = false;
+                server_exception.reset();
+                client_exception.reset();
+                return true;
+            }
+
            if (have_error)
            {
-                const auto * exception = server_exception ? server_exception.get() : client_exception.get();
                fmt::print(stderr, "Error on processing query '{}': {}\n", ast_to_process->formatForErrorMessage(), exception->message());

                // Try to reconnect after errors, for two reasons:
@ -2435,6 +2456,8 @@ public:
                    {
                        /// param_name value
                        ++arg_num;
+                        if (arg_num >= argc)
+                            throw Exception("Parameter requires value", ErrorCodes::BAD_ARGUMENTS);
                        arg = argv[arg_num];
                        query_parameters.emplace(String(param_continuation), String(arg));
                    }
--- a/programs/odbc-bridge/ODBCBlockInputStream.cpp
+++ b/programs/odbc-bridge/ODBCBlockInputStream.cpp
@ -115,6 +115,8 @@ void ODBCBlockInputStream::insertValue(
            assert_cast<ColumnFloat64 &>(column).insertValue(row.get<double>(idx));
            break;
        case ValueType::vtFixedString:[[fallthrough]];
+        case ValueType::vtEnum8:
+        case ValueType::vtEnum16:
        case ValueType::vtString:
            assert_cast<ColumnString &>(column).insert(row.get<std::string>(idx));
            break;
--- a/programs/server/Server.cpp
+++ b/programs/server/Server.cpp
@ -324,6 +324,13 @@ Poco::Net::SocketAddress Server::socketBindListen(Poco::Net::ServerSocket & sock
    socket.bind(address, /* reuseAddress = */ true, /* reusePort = */ config().getBool("listen_reuse_port", false));
 #endif

+    /// If caller requests any available port from the OS, discover it after binding.
+    if (port == 0)
+    {
+        address = socket.address();
+        LOG_DEBUG(&logger(), "Requested any available port (port == 0), actual port is {:d}", address.port());
+    }
+
    socket.listen(/* backlog = */ config().getUInt("listen_backlog", 64));

    return address;
@ -390,7 +397,7 @@ void Server::initialize(Poco::Util::Application & self)
    BaseDaemon::initialize(self);
    logger().information("starting up");

-    LOG_INFO(&logger(), "OS Name = {}, OS Version = {}, OS Architecture = {}",
+    LOG_INFO(&logger(), "OS name: {}, version: {}, architecture: {}",
        Poco::Environment::osName(),
        Poco::Environment::osVersion(),
        Poco::Environment::osArchitecture());
--- a/src/AggregateFunctions/AggregateFunctionGroupArray.cpp
+++ b/src/AggregateFunctions/AggregateFunctionGroupArray.cpp
@ -30,16 +30,16 @@ static IAggregateFunction * createWithNumericOrTimeType(const IDataType & argume


 template <typename Trait, typename ... TArgs>
-inline AggregateFunctionPtr createAggregateFunctionGroupArrayImpl(const DataTypePtr & argument_type, TArgs ... args)
+inline AggregateFunctionPtr createAggregateFunctionGroupArrayImpl(const DataTypePtr & argument_type, const Array & parameters, TArgs ... args)
 {
-    if (auto res = createWithNumericOrTimeType<GroupArrayNumericImpl, Trait>(*argument_type, argument_type, std::forward<TArgs>(args)...))
+    if (auto res = createWithNumericOrTimeType<GroupArrayNumericImpl, Trait>(*argument_type, argument_type, parameters, std::forward<TArgs>(args)...))
        return AggregateFunctionPtr(res);

    WhichDataType which(argument_type);
    if (which.idx == TypeIndex::String)
-        return std::make_shared<GroupArrayGeneralImpl<GroupArrayNodeString, Trait>>(argument_type, std::forward<TArgs>(args)...);
+        return std::make_shared<GroupArrayGeneralImpl<GroupArrayNodeString, Trait>>(argument_type, parameters, std::forward<TArgs>(args)...);

-    return std::make_shared<GroupArrayGeneralImpl<GroupArrayNodeGeneral, Trait>>(argument_type, std::forward<TArgs>(args)...);
+    return std::make_shared<GroupArrayGeneralImpl<GroupArrayNodeGeneral, Trait>>(argument_type, parameters, std::forward<TArgs>(args)...);

    // Link list implementation doesn't show noticeable performance improvement
    // if (which.idx == TypeIndex::String)
@ -79,9 +79,9 @@ AggregateFunctionPtr createAggregateFunctionGroupArray(
            ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);

    if (!limit_size)
-        return createAggregateFunctionGroupArrayImpl<GroupArrayTrait<false, Sampler::NONE>>(argument_types[0]);
+        return createAggregateFunctionGroupArrayImpl<GroupArrayTrait<false, Sampler::NONE>>(argument_types[0], parameters);
    else
-        return createAggregateFunctionGroupArrayImpl<GroupArrayTrait<true, Sampler::NONE>>(argument_types[0], max_elems);
+        return createAggregateFunctionGroupArrayImpl<GroupArrayTrait<true, Sampler::NONE>>(argument_types[0], parameters, max_elems);
 }

 AggregateFunctionPtr createAggregateFunctionGroupArraySample(
@ -114,7 +114,7 @@ AggregateFunctionPtr createAggregateFunctionGroupArraySample(
    else
        seed = thread_local_rng();

-    return createAggregateFunctionGroupArrayImpl<GroupArrayTrait<true, Sampler::RNG>>(argument_types[0], max_elems, seed);
+    return createAggregateFunctionGroupArrayImpl<GroupArrayTrait<true, Sampler::RNG>>(argument_types[0], parameters, max_elems, seed);
 }

 }
--- a/src/AggregateFunctions/AggregateFunctionGroupArray.h
+++ b/src/AggregateFunctions/AggregateFunctionGroupArray.h
@ -119,9 +119,9 @@ class GroupArrayNumericImpl final

 public:
    explicit GroupArrayNumericImpl(
-        const DataTypePtr & data_type_, UInt64 max_elems_ = std::numeric_limits<UInt64>::max(), UInt64 seed_ = 123456)
+        const DataTypePtr & data_type_, const Array & parameters_, UInt64 max_elems_ = std::numeric_limits<UInt64>::max(), UInt64 seed_ = 123456)
        : IAggregateFunctionDataHelper<GroupArrayNumericData<T, Trait::sampler != Sampler::NONE>, GroupArrayNumericImpl<T, Trait>>(
-            {data_type_}, {})
+            {data_type_}, parameters_)
        , max_elems(max_elems_)
        , seed(seed_)
    {
@ -421,9 +421,9 @@ class GroupArrayGeneralImpl final
    UInt64 seed;

 public:
-    GroupArrayGeneralImpl(const DataTypePtr & data_type_, UInt64 max_elems_ = std::numeric_limits<UInt64>::max(), UInt64 seed_ = 123456)
+    GroupArrayGeneralImpl(const DataTypePtr & data_type_, const Array & parameters_, UInt64 max_elems_ = std::numeric_limits<UInt64>::max(), UInt64 seed_ = 123456)
        : IAggregateFunctionDataHelper<GroupArrayGeneralData<Node, Trait::sampler != Sampler::NONE>, GroupArrayGeneralImpl<Node, Trait>>(
-            {data_type_}, {})
+            {data_type_}, parameters_)
        , data_type(this->argument_types[0])
        , max_elems(max_elems_)
        , seed(seed_)
@ -696,8 +696,8 @@ class GroupArrayGeneralListImpl final
    UInt64 max_elems;

 public:
-    GroupArrayGeneralListImpl(const DataTypePtr & data_type_, UInt64 max_elems_ = std::numeric_limits<UInt64>::max())
-        : IAggregateFunctionDataHelper<GroupArrayGeneralListData<Node>, GroupArrayGeneralListImpl<Node, Trait>>({data_type_}, {})
+    GroupArrayGeneralListImpl(const DataTypePtr & data_type_, const Array & parameters_, UInt64 max_elems_ = std::numeric_limits<UInt64>::max())
+        : IAggregateFunctionDataHelper<GroupArrayGeneralListData<Node>, GroupArrayGeneralListImpl<Node, Trait>>({data_type_}, parameters_)
        , data_type(this->argument_types[0])
        , max_elems(max_elems_)
    {
--- a/src/AggregateFunctions/AggregateFunctionGroupBitmapData.h
+++ b/src/AggregateFunctions/AggregateFunctionGroupBitmapData.h
@ -1,6 +1,7 @@
 #pragma once

 #include <algorithm>
+#include <memory>
 #include <boost/noncopyable.hpp>
 #include <IO/ReadHelpers.h>
 #include <IO/WriteHelpers.h>
@ -43,7 +44,7 @@ private:

    void toLarge()
    {
-        rb = std::make_shared<RoaringBitmap>();
+        rb = std::make_unique<RoaringBitmap>();
        for (const auto & x : small)
            rb->add(static_cast<Value>(x.getValue()));
        small.clear();
@ -113,7 +114,7 @@ public:
            readVarUInt(size, in);
            std::unique_ptr<char[]> buf(new char[size]);
            in.readStrict(buf.get(), size);
-            rb = std::make_shared<RoaringBitmap>(RoaringBitmap::read(buf.get()));
+            rb = std::make_unique<RoaringBitmap>(RoaringBitmap::read(buf.get()));
        }
    }

@ -140,7 +141,7 @@ public:
     */
    std::shared_ptr<RoaringBitmap> getNewRoaringBitmapFromSmall() const
    {
-        std::shared_ptr<RoaringBitmap> ret = std::make_shared<RoaringBitmap>();
+        std::shared_ptr<RoaringBitmap> ret = std::make_unique<RoaringBitmap>();
        for (const auto & x : small)
            ret->add(static_cast<Value>(x.getValue()));
        return ret;
--- a/src/Columns/Collator.h
+++ b/src/Columns/Collator.h
@ -1,6 +1,7 @@
 #pragma once

 #include <string>
+#include <optional>
 #include <vector>
 #include <boost/noncopyable.hpp>
 #include <unordered_map>
--- a/src/Columns/FilterDescription.cpp
+++ b/src/Columns/FilterDescription.cpp
@ -87,18 +87,4 @@ FilterDescription::FilterDescription(const IColumn & column_)
        ErrorCodes::ILLEGAL_TYPE_OF_COLUMN_FOR_FILTER);
 }

-
-void checkColumnCanBeUsedAsFilter(const ColumnWithTypeAndName & column_elem)
-{
-    ConstantFilterDescription const_filter;
-    if (column_elem.column)
-        const_filter = ConstantFilterDescription(*column_elem.column);
-
-    if (!const_filter.always_false && !const_filter.always_true)
-    {
-        auto column = column_elem.column ? column_elem.column : column_elem.type->createColumn();
-        FilterDescription filter(*column);
-    }
-}
-
 }
--- a/src/Columns/FilterDescription.h
+++ b/src/Columns/FilterDescription.h
@ -32,7 +32,4 @@ struct FilterDescription

 struct ColumnWithTypeAndName;

-/// Will throw an exception if column_elem is cannot be used as a filter column.
-void checkColumnCanBeUsedAsFilter(const ColumnWithTypeAndName & column_elem);
-
 }
--- a/src/Common/ErrorCodes.cpp
+++ b/src/Common/ErrorCodes.cpp
@ -555,6 +555,8 @@
    M(585, CANNOT_PARSE_YAML) \
    M(586, CANNOT_CREATE_FILE) \
    M(587, CONCURRENT_ACCESS_NOT_SUPPORTED) \
+    M(588, DISTRIBUTED_BROKEN_BATCH_INFO) \
+    M(589, DISTRIBUTED_BROKEN_BATCH_FILES) \
    \
    M(998, POSTGRESQL_CONNECTION_FAILURE) \
    M(999, KEEPER_EXCEPTION) \
--- a/src/Common/ThreadStatus.cpp
+++ b/src/Common/ThreadStatus.cpp
@ -60,7 +60,8 @@ struct ThreadStack
    void * getData() const { return data; }

 private:
-    static constexpr size_t size = 16 << 10; /// 16 KiB - not too big but enough to handle error.
+    /// 16 KiB - not too big but enough to handle error.
+    static constexpr size_t size = std::max<size_t>(16 << 10, MINSIGSTKSZ);
    void * data;
 };

--- a/src/Common/checkStackSize.cpp
+++ b/src/Common/checkStackSize.cpp
@ -44,7 +44,7 @@ size_t getStackSize(void ** out_address)
    size = pthread_main_np() ? (8 * 1024 * 1024) : pthread_get_stacksize_np(thread);

    // stack address points to the start of the stack, not the end how it's returned by pthread_get_stackaddr_np
-    address = reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(pthread_get_stackaddr_np(thread)) - max_stack_size);
+    address = reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(pthread_get_stackaddr_np(thread)) - size);
 #else
    pthread_attr_t attr;
 #   if defined(__FreeBSD__) || defined(OS_SUNOS)
--- a/src/Compression/CompressedReadBufferBase.cpp
+++ b/src/Compression/CompressedReadBufferBase.cpp
@ -59,7 +59,7 @@ static void validateChecksum(char * data, size_t size, const Checksum expected_c
                                            "or bad RAM on host (look at dmesg or kern.log for enormous amount of EDAC errors, "
                                            "ECC-related reports, Machine Check Exceptions, mcelog; note that ECC memory can fail "
                                            "if the number of errors is huge) or bad CPU on host. If you read data from disk, "
-                                            "this can be caused by disk bit rott. This exception protects ClickHouse "
+                                            "this can be caused by disk bit rot. This exception protects ClickHouse "
                                            "from data corruption due to hardware failures.";

    auto flip_bit = [](char * buf, size_t pos)
--- a/src/Coordination/Changelog.h
+++ b/src/Coordination/Changelog.h
@ -23,9 +23,10 @@ using IndexToLogEntry = std::unordered_map<uint64_t, LogEntryPtr>;
 enum class ChangelogVersion : uint8_t
 {
    V0 = 0,
+    V1 = 1, /// with 64 bit buffer header
 };

-static constexpr auto CURRENT_CHANGELOG_VERSION = ChangelogVersion::V0;
+static constexpr auto CURRENT_CHANGELOG_VERSION = ChangelogVersion::V1;

 struct ChangelogRecordHeader
 {
--- a/src/Coordination/KeeperSnapshotManager.cpp
+++ b/src/Coordination/KeeperSnapshotManager.cpp
@ -204,7 +204,7 @@ SnapshotMetadataPtr KeeperStorageSnapshot::deserialize(KeeperStorage & storage,
    uint8_t version;
    readBinary(version, in);
    SnapshotVersion current_version = static_cast<SnapshotVersion>(version);
-    if (current_version > SnapshotVersion::V1)
+    if (current_version > CURRENT_SNAPSHOT_VERSION)
        throw Exception(ErrorCodes::UNKNOWN_FORMAT_VERSION, "Unsupported snapshot version {}", version);

    SnapshotMetadataPtr result = deserializeSnapshotMetadata(in);
--- a/src/Coordination/KeeperSnapshotManager.h
+++ b/src/Coordination/KeeperSnapshotManager.h
@ -14,8 +14,11 @@ enum SnapshotVersion : uint8_t
 {
    V0 = 0,
    V1 = 1, /// with ACL map
+    V2 = 2, /// with 64 bit buffer header
 };

+static constexpr auto CURRENT_SNAPSHOT_VERSION = SnapshotVersion::V2;
+
 struct KeeperStorageSnapshot
 {
 public:
@ -30,7 +33,7 @@ public:

    KeeperStorage * storage;

-    SnapshotVersion version = SnapshotVersion::V1;
+    SnapshotVersion version = CURRENT_SNAPSHOT_VERSION;
    SnapshotMetadataPtr snapshot_meta;
    int64_t session_id;
    size_t snapshot_container_size;
--- a/src/Core/ExternalResultDescription.cpp
+++ b/src/Core/ExternalResultDescription.cpp
@ -69,9 +69,9 @@ void ExternalResultDescription::init(const Block & sample_block_)
        else if (which.isUUID())
            types.emplace_back(ValueType::vtUUID, is_nullable);
        else if (which.isEnum8())
-            types.emplace_back(ValueType::vtString, is_nullable);
+            types.emplace_back(ValueType::vtEnum8, is_nullable);
        else if (which.isEnum16())
-            types.emplace_back(ValueType::vtString, is_nullable);
+            types.emplace_back(ValueType::vtEnum16, is_nullable);
        else if (which.isDateTime64())
            types.emplace_back(ValueType::vtDateTime64, is_nullable);
        else if (which.isDecimal32())
--- a/src/Core/ExternalResultDescription.h
+++ b/src/Core/ExternalResultDescription.h
@ -22,6 +22,8 @@ struct ExternalResultDescription
        vtInt64,
        vtFloat32,
        vtFloat64,
+        vtEnum8,
+        vtEnum16,
        vtString,
        vtDate,
        vtDate32,
--- a/src/Core/MySQL/MySQLReplication.cpp
+++ b/src/Core/MySQL/MySQLReplication.cpp
@ -298,7 +298,6 @@ namespace MySQLReplication
    }

    /// Types that do not used in the binlog event:
-    /// MYSQL_TYPE_ENUM
    /// MYSQL_TYPE_SET
    /// MYSQL_TYPE_TINY_BLOB
    /// MYSQL_TYPE_MEDIUM_BLOB
@ -562,6 +561,22 @@ namespace MySQLReplication
                        row.push_back(dispatch((meta >> 8) & 0xFF, meta & 0xFF, read_decimal));
                        break;
                    }
+                    case MYSQL_TYPE_ENUM:
+                    {
+                        if ((meta & 0xFF) == 1)
+                        {
+                            UInt8 val = 0;
+                            payload.readStrict(reinterpret_cast<char *>(&val), 1);
+                            row.push_back(Field{UInt8{val}});
+                        }
+                        else
+                        {
+                            UInt16 val = 0;
+                            payload.readStrict(reinterpret_cast<char *>(&val), 2);
+                            row.push_back(Field{UInt16{val}});
+                        }
+                        break;
+                    }
                    case MYSQL_TYPE_VARCHAR:
                    case MYSQL_TYPE_VAR_STRING:
                    {
--- a/Show More
+++ b/Show More