diff --git a/dbms/programs/server/MySQLHandler.cpp b/dbms/programs/server/MySQLHandler.cpp
index f9aa29ab0b5..611d811b21d 100644
--- a/dbms/programs/server/MySQLHandler.cpp
+++ b/dbms/programs/server/MySQLHandler.cpp
@@ -305,9 +305,9 @@ void MySQLHandler::authenticate(const HandshakeResponse & handshake_response, co
         LOG_TRACE(log, "Received empty password");
     }
 
-    if (!password.empty())
+    if (!password.empty() && password.back() == 0)
     {
-        password.pop_back(); /// terminating null byte
+        password.pop_back();
     }
 
     try
diff --git a/dbms/src/Interpreters/AsteriskSemantic.h b/dbms/src/Interpreters/AsteriskSemantic.h
index c0928a42691..1bd9ecedddd 100644
--- a/dbms/src/Interpreters/AsteriskSemantic.h
+++ b/dbms/src/Interpreters/AsteriskSemantic.h
@@ -4,6 +4,7 @@
 
 #include <Parsers/ASTAsterisk.h>
 #include <Parsers/ASTQualifiedAsterisk.h>
+#include <Parsers/ASTColumnsMatcher.h>
 
 namespace DB
 {
@@ -24,9 +25,11 @@ struct AsteriskSemantic
 
     static void setAliases(ASTAsterisk & node, const RevertedAliasesPtr & aliases) { node.semantic = makeSemantic(aliases); }
     static void setAliases(ASTQualifiedAsterisk & node, const RevertedAliasesPtr & aliases) { node.semantic = makeSemantic(aliases); }
+    static void setAliases(ASTColumnsMatcher & node, const RevertedAliasesPtr & aliases) { node.semantic = makeSemantic(aliases); }
 
     static RevertedAliasesPtr getAliases(const ASTAsterisk & node) { return node.semantic ? node.semantic->aliases : nullptr; }
     static RevertedAliasesPtr getAliases(const ASTQualifiedAsterisk & node) { return node.semantic ? node.semantic->aliases : nullptr; }
+    static RevertedAliasesPtr getAliases(const ASTColumnsMatcher & node) { return node.semantic ? node.semantic->aliases : nullptr; }
 
 private:
     static std::shared_ptr<AsteriskSemanticImpl> makeSemantic(const RevertedAliasesPtr & aliases)
diff --git a/dbms/src/Interpreters/ExpressionAnalyzer.cpp b/dbms/src/Interpreters/ExpressionAnalyzer.cpp
index e8143f3c41a..055f5c8f3ec 100644
--- a/dbms/src/Interpreters/ExpressionAnalyzer.cpp
+++ b/dbms/src/Interpreters/ExpressionAnalyzer.cpp
@@ -6,7 +6,6 @@
 #include <Parsers/ASTFunction.h>
 #include <Parsers/ASTIdentifier.h>
 #include <Parsers/ASTLiteral.h>
-#include <Parsers/ASTAsterisk.h>
 #include <Parsers/ASTQualifiedAsterisk.h>
 #include <Parsers/ASTExpressionList.h>
 #include <Parsers/ASTSelectQuery.h>
diff --git a/dbms/src/Interpreters/ExternalLoader.cpp b/dbms/src/Interpreters/ExternalLoader.cpp
index c7b3d202a28..31a69086f5c 100644
--- a/dbms/src/Interpreters/ExternalLoader.cpp
+++ b/dbms/src/Interpreters/ExternalLoader.cpp
@@ -511,12 +511,14 @@ public:
     {
         std::lock_guard lock{mutex};
         for (auto & [name, info] : infos)
+        {
             if ((info.was_loading() || load_never_loading) && filter_by_name(name))
             {
                 cancelLoading(info);
                 info.forced_to_reload = true;
                 startLoading(name, info);
             }
+        }
     }
 
     /// Starts reloading of all the objects.
@@ -528,20 +530,22 @@ public:
     /// The function doesn't touch the objects which were never tried to load.
     void reloadOutdated()
     {
+        /// Iterate through all the objects and find loaded ones which should be checked if they were modified.
         std::unordered_map<LoadablePtr, bool> is_modified_map;
-
         {
             std::lock_guard lock{mutex};
             TimePoint now = std::chrono::system_clock::now();
             for (const auto & name_and_info : infos)
             {
                 const auto & info = name_and_info.second;
-                if ((now >= info.next_update_time) && !info.loading() && info.was_loading())
+                if ((now >= info.next_update_time) && !info.loading() && info.loaded())
                     is_modified_map.emplace(info.object, true);
             }
         }
 
-        /// The `mutex` should be unlocked while we're calling the function is_object_modified().
+        /// Find out which of the loaded objects were modified.
+        /// We couldn't perform these checks while we were building `is_modified_map` because
+        /// the `mutex` should be unlocked while we're calling the function is_object_modified().
         for (auto & [object, is_modified_flag] : is_modified_map)
         {
             try
@@ -554,21 +558,38 @@ public:
             }
         }
 
+        /// Iterate through all the objects again and either start loading or just set `next_update_time`.
         {
             std::lock_guard lock{mutex};
             TimePoint now = std::chrono::system_clock::now();
             for (auto & [name, info] : infos)
-                if ((now >= info.next_update_time) && !info.loading() && info.was_loading())
+            {
+                if ((now >= info.next_update_time) && !info.loading())
                 {
-                    auto it = is_modified_map.find(info.object);
-                    if (it == is_modified_map.end())
-                        continue; /// Object has been just added, it can be simply omitted from this update of outdated.
-                    bool is_modified_flag = it->second;
-                    if (info.loaded() && !is_modified_flag)
-                        info.next_update_time = calculate_next_update_time(info.object, info.error_count);
-                    else
+                    if (info.loaded())
+                    {
+                        auto it = is_modified_map.find(info.object);
+                        if (it == is_modified_map.end())
+                            continue; /// Object has been just loaded (it wasn't loaded while we were building the map `is_modified_map`), so we don't have to reload it right now.
+
+                        bool is_modified_flag = it->second;
+                        if (!is_modified_flag)
+                        {
+                            /// Object wasn't modified so we only have to set `next_update_time`.
+                            info.next_update_time = calculate_next_update_time(info.object, info.error_count);
+                            continue;
+                        }
+
+                        /// Object was modified and should be reloaded.
                         startLoading(name, info);
+                    }
+                    else if (info.failed())
+                    {
+                        /// Object was never loaded successfully and should be reloaded.
+                        startLoading(name, info);
+                    }
                 }
+            }
         }
     }
 
diff --git a/dbms/src/Interpreters/PredicateExpressionsOptimizer.cpp b/dbms/src/Interpreters/PredicateExpressionsOptimizer.cpp
index 3d2f465bde8..b6e6545e475 100644
--- a/dbms/src/Interpreters/PredicateExpressionsOptimizer.cpp
+++ b/dbms/src/Interpreters/PredicateExpressionsOptimizer.cpp
@@ -15,6 +15,7 @@
 #include <Parsers/ASTTablesInSelectQuery.h>
 #include <Parsers/ASTAsterisk.h>
 #include <Parsers/ASTQualifiedAsterisk.h>
+#include <Parsers/ASTColumnsMatcher.h>
 #include <Parsers/queryToString.h>
 #include <Interpreters/Context.h>
 #include <Interpreters/ExpressionActions.h>
@@ -25,6 +26,7 @@
 #include <Interpreters/ExtractFunctionDataVisitor.h>
 #include <Functions/FunctionFactory.h>
 
+
 namespace DB
 {
 
@@ -266,7 +268,7 @@ std::vector<ASTPtr> PredicateExpressionsOptimizer::splitConjunctionPredicate(con
                     continue;
                 }
             }
-            idx++;
+            ++idx;
         }
     }
     return predicate_expressions;
@@ -412,7 +414,7 @@ ASTs PredicateExpressionsOptimizer::getSelectQueryProjectionColumns(ASTPtr & ast
 
     for (const auto & projection_column : select_query->select()->children)
     {
-        if (projection_column->as<ASTAsterisk>() || projection_column->as<ASTQualifiedAsterisk>())
+        if (projection_column->as<ASTAsterisk>() || projection_column->as<ASTQualifiedAsterisk>() || projection_column->as<ASTColumnsMatcher>())
         {
             ASTs evaluated_columns = evaluateAsterisk(select_query, projection_column);
 
@@ -483,8 +485,20 @@ ASTs PredicateExpressionsOptimizer::evaluateAsterisk(ASTSelectQuery * select_que
                 throw Exception("Logical error: unexpected table expression", ErrorCodes::LOGICAL_ERROR);
 
             const auto block = storage->getSampleBlock();
-            for (size_t idx = 0; idx < block.columns(); idx++)
-                projection_columns.emplace_back(std::make_shared<ASTIdentifier>(block.getByPosition(idx).name));
+            if (const auto * asterisk_pattern = asterisk->as<ASTColumnsMatcher>())
+            {
+                for (size_t idx = 0; idx < block.columns(); ++idx)
+                {
+                    auto & col = block.getByPosition(idx);
+                    if (asterisk_pattern->isColumnMatching(col.name))
+                        projection_columns.emplace_back(std::make_shared<ASTIdentifier>(col.name));
+                }
+            }
+            else
+            {
+                for (size_t idx = 0; idx < block.columns(); ++idx)
+                    projection_columns.emplace_back(std::make_shared<ASTIdentifier>(block.getByPosition(idx).name));
+            }
         }
     }
     return projection_columns;
diff --git a/dbms/src/Interpreters/QueryNormalizer.cpp b/dbms/src/Interpreters/QueryNormalizer.cpp
index c35c47179c6..cea801c7c2f 100644
--- a/dbms/src/Interpreters/QueryNormalizer.cpp
+++ b/dbms/src/Interpreters/QueryNormalizer.cpp
@@ -4,7 +4,6 @@
 #include <Interpreters/IdentifierSemantic.h>
 #include <Interpreters/Context.h>
 #include <Interpreters/AnalyzedJoin.h>
-#include <Parsers/ASTAsterisk.h>
 #include <Parsers/ASTFunction.h>
 #include <Parsers/ASTIdentifier.h>
 #include <Parsers/ASTSelectQuery.h>
diff --git a/dbms/src/Interpreters/SyntaxAnalyzer.cpp b/dbms/src/Interpreters/SyntaxAnalyzer.cpp
index 62982ea1e59..83cacc94692 100644
--- a/dbms/src/Interpreters/SyntaxAnalyzer.cpp
+++ b/dbms/src/Interpreters/SyntaxAnalyzer.cpp
@@ -41,6 +41,7 @@ namespace ErrorCodes
     extern const int EMPTY_NESTED_TABLE;
     extern const int LOGICAL_ERROR;
     extern const int INVALID_JOIN_ON_EXPRESSION;
+    extern const int EMPTY_LIST_OF_COLUMNS_QUERIED;
 }
 
 NameSet removeDuplicateColumns(NamesAndTypesList & columns)
@@ -110,6 +111,10 @@ void translateQualifiedNames(ASTPtr & query, const ASTSelectQuery & select_query
     TranslateQualifiedNamesVisitor::Data visitor_data(source_columns_set, tables_with_columns);
     TranslateQualifiedNamesVisitor visitor(visitor_data, log.stream());
     visitor.visit(query);
+
+    /// This may happen after expansion of COLUMNS('regexp').
+    if (select_query.select()->children.empty())
+        throw Exception("Empty list of columns in SELECT query", ErrorCodes::EMPTY_LIST_OF_COLUMNS_QUERIED);
 }
 
 bool hasArrayJoin(const ASTPtr & ast)
diff --git a/dbms/src/Interpreters/TranslateQualifiedNamesVisitor.cpp b/dbms/src/Interpreters/TranslateQualifiedNamesVisitor.cpp
index e2d38422ef1..1b063bc4625 100644
--- a/dbms/src/Interpreters/TranslateQualifiedNamesVisitor.cpp
+++ b/dbms/src/Interpreters/TranslateQualifiedNamesVisitor.cpp
@@ -16,7 +16,7 @@
 #include <Parsers/ASTExpressionList.h>
 #include <Parsers/ASTLiteral.h>
 #include <Parsers/ASTFunction.h>
-#include <iostream>
+#include <Parsers/ASTColumnsMatcher.h>
 
 
 namespace DB
@@ -124,7 +124,6 @@ void TranslateQualifiedNamesMatcher::visit(ASTSelectQuery & select, const ASTPtr
     if (auto join = select.join())
         extractJoinUsingColumns(join->table_join, data);
 
-#if 1 /// TODO: legacy?
     /// If the WHERE clause or HAVING consists of a single qualified column, the reference must be translated not only in children,
     /// but also in where_expression and having_expression.
     if (select.prewhere())
@@ -133,7 +132,6 @@ void TranslateQualifiedNamesMatcher::visit(ASTSelectQuery & select, const ASTPtr
         Visitor(data).visit(select.refWhere());
     if (select.having())
         Visitor(data).visit(select.refHaving());
-#endif
 }
 
 static void addIdentifier(ASTs & nodes, const String & table_name, const String & column_name, AsteriskSemantic::RevertedAliasesPtr aliases)
@@ -166,7 +164,7 @@ void TranslateQualifiedNamesMatcher::visit(ASTExpressionList & node, const ASTPt
         bool has_asterisk = false;
         for (const auto & child : node.children)
         {
-            if (child->as<ASTAsterisk>())
+            if (child->as<ASTAsterisk>() || child->as<ASTColumnsMatcher>())
             {
                 if (tables_with_columns.empty())
                     throw Exception("An asterisk cannot be replaced with empty columns.", ErrorCodes::LOGICAL_ERROR);
@@ -207,6 +205,23 @@ void TranslateQualifiedNamesMatcher::visit(ASTExpressionList & node, const ASTPt
                 first_table = false;
             }
         }
+        else if (const auto * asterisk_pattern = child->as<ASTColumnsMatcher>())
+        {
+            bool first_table = true;
+            for (const auto & [table, table_columns] : tables_with_columns)
+            {
+                for (const auto & column_name : table_columns)
+                {
+                    if (asterisk_pattern->isColumnMatching(column_name) && (first_table || !data.join_using_columns.count(column_name)))
+                    {
+                        String table_name = table.getQualifiedNamePrefix(false);
+                        addIdentifier(node.children, table_name, column_name, AsteriskSemantic::getAliases(*asterisk_pattern));
+                    }
+                }
+
+                first_table = false;
+            }
+        }
         else if (const auto * qualified_asterisk = child->as<ASTQualifiedAsterisk>())
         {
             DatabaseAndTableWithAlias ident_db_and_name(qualified_asterisk->children[0]);
diff --git a/dbms/src/Parsers/ASTColumnsMatcher.cpp b/dbms/src/Parsers/ASTColumnsMatcher.cpp
new file mode 100644
index 00000000000..e9cdb822c6e
--- /dev/null
+++ b/dbms/src/Parsers/ASTColumnsMatcher.cpp
@@ -0,0 +1,45 @@
+#include "ASTColumnsMatcher.h"
+
+#include <IO/WriteBuffer.h>
+#include <IO/WriteHelpers.h>
+#include <IO/WriteBufferFromString.h>
+
+#include <re2/re2.h>
+
+
+
+namespace DB
+{
+
+ASTPtr ASTColumnsMatcher::clone() const
+{
+    auto clone = std::make_shared<ASTColumnsMatcher>(*this);
+    clone->cloneChildren();
+    return clone;
+}
+
+void ASTColumnsMatcher::appendColumnName(WriteBuffer & ostr) const { writeString(original_pattern, ostr); }
+
+void ASTColumnsMatcher::formatImpl(const FormatSettings & settings, FormatState &, FormatStateStacked) const
+{
+    WriteBufferFromOwnString pattern_quoted;
+    writeQuotedString(original_pattern, pattern_quoted);
+
+    settings.ostr << (settings.hilite ? hilite_keyword : "") << "COLUMNS" << (settings.hilite ? hilite_none : "") << "(" << pattern_quoted.str() << ")";
+}
+
+void ASTColumnsMatcher::setPattern(String pattern)
+{
+    original_pattern = std::move(pattern);
+    column_matcher = std::make_shared<RE2>(original_pattern, RE2::Quiet);
+    if (!column_matcher->ok())
+        throw DB::Exception("COLUMNS pattern " + original_pattern + " cannot be compiled: " + column_matcher->error(), DB::ErrorCodes::CANNOT_COMPILE_REGEXP);
+}
+
+bool ASTColumnsMatcher::isColumnMatching(const String & column_name) const
+{
+    return RE2::PartialMatch(column_name, *column_matcher);
+}
+
+
+}
diff --git a/dbms/src/Parsers/ASTColumnsMatcher.h b/dbms/src/Parsers/ASTColumnsMatcher.h
new file mode 100644
index 00000000000..e5ec9a2873d
--- /dev/null
+++ b/dbms/src/Parsers/ASTColumnsMatcher.h
@@ -0,0 +1,50 @@
+#pragma once
+
+#include <Parsers/IAST.h>
+
+
+namespace re2
+{
+    class RE2;
+}
+
+
+namespace DB
+{
+
+class WriteBuffer;
+
+namespace ErrorCodes
+{
+    extern const int CANNOT_COMPILE_REGEXP;
+}
+
+struct AsteriskSemantic;
+struct AsteriskSemanticImpl;
+
+
+/** SELECT COLUMNS('regexp') is expanded to multiple columns like * (asterisk).
+  */
+class ASTColumnsMatcher : public IAST
+{
+public:
+    String getID(char) const override { return "ColumnsMatcher"; }
+    ASTPtr clone() const override;
+
+    void appendColumnName(WriteBuffer & ostr) const override;
+    void setPattern(String pattern);
+    bool isColumnMatching(const String & column_name) const;
+
+protected:
+    void formatImpl(const FormatSettings & settings, FormatState &, FormatStateStacked) const override;
+
+private:
+    std::shared_ptr<re2::RE2> column_matcher;
+    String original_pattern;
+    std::shared_ptr<AsteriskSemanticImpl> semantic; /// pimpl
+
+    friend struct AsteriskSemantic;
+};
+
+
+}
diff --git a/dbms/src/Parsers/ASTSelectQuery.cpp b/dbms/src/Parsers/ASTSelectQuery.cpp
index 44012cd071c..16396095ce9 100644
--- a/dbms/src/Parsers/ASTSelectQuery.cpp
+++ b/dbms/src/Parsers/ASTSelectQuery.cpp
@@ -1,7 +1,6 @@
 #include <Common/typeid_cast.h>
 #include <Parsers/ASTSetQuery.h>
 #include <Parsers/ASTFunction.h>
-#include <Parsers/ASTAsterisk.h>
 #include <Parsers/ASTIdentifier.h>
 #include <Parsers/ASTSelectQuery.h>
 #include <Parsers/ASTTablesInSelectQuery.h>
diff --git a/dbms/src/Parsers/ExpressionElementParsers.cpp b/dbms/src/Parsers/ExpressionElementParsers.cpp
index 9c0071c64e8..8cd017f0710 100644
--- a/dbms/src/Parsers/ExpressionElementParsers.cpp
+++ b/dbms/src/Parsers/ExpressionElementParsers.cpp
@@ -29,6 +29,7 @@
 
 #include <Parsers/queryToString.h>
 #include <boost/algorithm/string.hpp>
+#include "ASTColumnsMatcher.h"
 
 
 namespace DB
@@ -1168,6 +1169,34 @@ bool ParserAlias::parseImpl(Pos & pos, ASTPtr & node, Expected & expected)
 }
 
 
+bool ParserColumnsMatcher::parseImpl(Pos & pos, ASTPtr & node, Expected & expected)
+{
+    ParserKeyword columns("COLUMNS");
+    ParserStringLiteral regex;
+
+    if (!columns.ignore(pos, expected))
+        return false;
+
+    if (pos->type != TokenType::OpeningRoundBracket)
+        return false;
+    ++pos;
+
+    ASTPtr regex_node;
+    if (!regex.parse(pos, regex_node, expected))
+        return false;
+
+    if (pos->type != TokenType::ClosingRoundBracket)
+        return false;
+    ++pos;
+
+    auto res = std::make_shared<ASTColumnsMatcher>();
+    res->setPattern(regex_node->as<ASTLiteral &>().value.get<String>());
+    res->children.push_back(regex_node);
+    node = std::move(res);
+    return true;
+}
+
+
 bool ParserAsterisk::parseImpl(Pos & pos, ASTPtr & node, Expected &)
 {
     if (pos->type == TokenType::Asterisk)
@@ -1262,6 +1291,7 @@ bool ParserExpressionElement::parseImpl(Pos & pos, ASTPtr & node, Expected & exp
         || ParserLeftExpression().parse(pos, node, expected)
         || ParserRightExpression().parse(pos, node, expected)
         || ParserCase().parse(pos, node, expected)
+        || ParserColumnsMatcher().parse(pos, node, expected) /// before ParserFunction because it can be also parsed as a function.
         || ParserFunction().parse(pos, node, expected)
         || ParserQualifiedAsterisk().parse(pos, node, expected)
         || ParserAsterisk().parse(pos, node, expected)
diff --git a/dbms/src/Parsers/ExpressionElementParsers.h b/dbms/src/Parsers/ExpressionElementParsers.h
index b4fe77e8bb3..dca82f72f12 100644
--- a/dbms/src/Parsers/ExpressionElementParsers.h
+++ b/dbms/src/Parsers/ExpressionElementParsers.h
@@ -56,7 +56,6 @@ protected:
     bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected);
 };
 
-
 /// Just *
 class ParserAsterisk : public IParserBase
 {
@@ -65,7 +64,6 @@ protected:
     bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected);
 };
 
-
 /** Something like t.* or db.table.*
   */
 class ParserQualifiedAsterisk : public IParserBase
@@ -75,6 +73,14 @@ protected:
     bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected);
 };
 
+/** COLUMNS('<regular expression>')
+  */
+class ParserColumnsMatcher : public IParserBase
+{
+protected:
+    const char * getName() const { return "COLUMNS matcher"; }
+    bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected);
+};
 
 /** A function, for example, f(x, y + 1, g(z)).
   * Or an aggregate function: sum(x + f(y)), corr(x, y). The syntax is the same as the usual function.
diff --git a/dbms/src/Storages/StorageMergeTree.cpp b/dbms/src/Storages/StorageMergeTree.cpp
index d021866487c..0536423101d 100644
--- a/dbms/src/Storages/StorageMergeTree.cpp
+++ b/dbms/src/Storages/StorageMergeTree.cpp
@@ -530,7 +530,11 @@ bool StorageMergeTree::merge(
         }
 
         if (!selected)
+        {
+            if (out_disable_reason)
+                *out_disable_reason = "Cannot select parts for optimization";
             return false;
+        }
 
         merging_tagger.emplace(future_part, MergeTreeDataMergerMutator::estimateNeededDiskSpace(future_part.parts), *this);
     }
@@ -886,8 +890,16 @@ bool StorageMergeTree::optimize(
         {
             if (!merge(true, partition_id, true, deduplicate, &disable_reason))
             {
+                std::stringstream message;
+                message << "Cannot OPTIMIZE table";
+                if (!disable_reason.empty())
+                    message << ": " << disable_reason;
+                else
+                    message << " by some reason.";
+                LOG_INFO(log, message.rdbuf());
+
                 if (context.getSettingsRef().optimize_throw_if_noop)
-                    throw Exception(disable_reason.empty() ? "Can't OPTIMIZE by some reason" : disable_reason, ErrorCodes::CANNOT_ASSIGN_OPTIMIZE);
+                    throw Exception(message.str(), ErrorCodes::CANNOT_ASSIGN_OPTIMIZE);
                 return false;
             }
         }
@@ -900,8 +912,16 @@ bool StorageMergeTree::optimize(
 
         if (!merge(true, partition_id, final, deduplicate, &disable_reason))
         {
+            std::stringstream message;
+            message << "Cannot OPTIMIZE table";
+            if (!disable_reason.empty())
+                message << ": " << disable_reason;
+            else
+                message << " by some reason.";
+            LOG_INFO(log, message.rdbuf());
+
             if (context.getSettingsRef().optimize_throw_if_noop)
-                throw Exception(disable_reason.empty() ? "Can't OPTIMIZE by some reason" : disable_reason, ErrorCodes::CANNOT_ASSIGN_OPTIMIZE);
+                throw Exception(message.str(), ErrorCodes::CANNOT_ASSIGN_OPTIMIZE);
             return false;
         }
     }
diff --git a/dbms/src/Storages/StorageReplicatedMergeTree.cpp b/dbms/src/Storages/StorageReplicatedMergeTree.cpp
index b51da168192..934d651fead 100644
--- a/dbms/src/Storages/StorageReplicatedMergeTree.cpp
+++ b/dbms/src/Storages/StorageReplicatedMergeTree.cpp
@@ -3042,8 +3042,12 @@ bool StorageReplicatedMergeTree::optimize(const ASTPtr & query, const ASTPtr & p
 
             if (!selected)
             {
-                LOG_INFO(log, "Cannot select parts for optimization" + (disable_reason.empty() ? "" : ": " + disable_reason));
-                return handle_noop(disable_reason);
+                std::stringstream message;
+                message << "Cannot select parts for optimization";
+                if (!disable_reason.empty())
+                    message << ": " << disable_reason;
+                LOG_INFO(log, message.rdbuf());
+                return handle_noop(message.str());
             }
 
             ReplicatedMergeTreeLogEntryData merge_entry;
diff --git a/dbms/src/Storages/StorageView.cpp b/dbms/src/Storages/StorageView.cpp
index 9d4855b586a..153de1ab176 100644
--- a/dbms/src/Storages/StorageView.cpp
+++ b/dbms/src/Storages/StorageView.cpp
@@ -1,9 +1,12 @@
 #include <Interpreters/InterpreterSelectQuery.h>
 #include <Interpreters/InterpreterSelectWithUnionQuery.h>
+#include <Interpreters/PredicateExpressionsOptimizer.h>
+
 #include <Parsers/ASTCreateQuery.h>
 #include <Parsers/ASTSubquery.h>
 #include <Parsers/ASTTablesInSelectQuery.h>
 #include <Parsers/ASTSelectWithUnionQuery.h>
+#include <Parsers/queryToString.h>
 
 #include <Storages/StorageView.h>
 #include <Storages/StorageFactory.h>
@@ -11,10 +14,7 @@
 #include <DataStreams/MaterializingBlockInputStream.h>
 
 #include <Common/typeid_cast.h>
-#include <Interpreters/PredicateExpressionsOptimizer.h>
-#include <Parsers/ASTAsterisk.h>
-#include <iostream>
-#include <Parsers/queryToString.h>
+
 
 namespace DB
 {
diff --git a/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/Dockerfile b/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/Dockerfile
new file mode 100644
index 00000000000..85e256dfed6
--- /dev/null
+++ b/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/Dockerfile
@@ -0,0 +1,7 @@
+FROM php:7.3-cli
+
+COPY ./client.crt client.crt
+COPY ./client.key client.key
+COPY ./test.php test.php
+
+RUN docker-php-ext-install pdo pdo_mysql
diff --git a/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/client.crt b/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/client.crt
new file mode 100644
index 00000000000..6f4deca038f
--- /dev/null
+++ b/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/client.crt
@@ -0,0 +1,18 @@
+-----BEGIN CERTIFICATE-----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=
+-----END CERTIFICATE-----
diff --git a/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/client.key b/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/client.key
new file mode 100644
index 00000000000..6eddb3295db
--- /dev/null
+++ b/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/client.key
@@ -0,0 +1,28 @@
+-----BEGIN PRIVATE KEY-----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+-----END PRIVATE KEY-----
diff --git a/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/docker_compose.yml b/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/docker_compose.yml
new file mode 100644
index 00000000000..28145864024
--- /dev/null
+++ b/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/docker_compose.yml
@@ -0,0 +1,7 @@
+version: '2.2'
+services:
+  php1:
+    build:
+      context: ./
+    # to keep container running
+    command: sleep infinity
diff --git a/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/test.php b/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/test.php
new file mode 100644
index 00000000000..86354381835
--- /dev/null
+++ b/dbms/tests/integration/test_mysql_protocol/clients/php-mysqlnd/test.php
@@ -0,0 +1,27 @@
+<?php
+$host = $argv[1];
+$db   = "system";
+$user = $argv[3];
+$pass = $argv[4];
+$charset = "utf8mb4";
+$port = $argv[2];
+
+$dsn = "mysql:host=$host;port=$port;dbname=$db;charset=$charset";
+$options = [
+    PDO::ATTR_ERRMODE            => PDO::ERRMODE_EXCEPTION,
+    PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
+    PDO::ATTR_EMULATE_PREPARES   => false,
+    PDO::MYSQL_ATTR_DIRECT_QUERY => true,
+    PDO::MYSQL_ATTR_SSL_CERT     => "client.crt",
+    PDO::MYSQL_ATTR_SSL_KEY      => "client.key",
+    PDO::MYSQL_ATTR_SSL_VERIFY_SERVER_CERT => 0,
+];
+$pdo = new PDO($dsn, $user, $pass, $options);
+
+$stmt = $pdo->query("SELECT name FROM tables WHERE name = 'tables'");
+
+foreach ($stmt as $row)
+{
+    echo $row["name"] . "\n";
+}
+?>
diff --git a/dbms/tests/integration/test_mysql_protocol/test.py b/dbms/tests/integration/test_mysql_protocol/test.py
index 04e6ac1ee8b..f0c696b4dc7 100644
--- a/dbms/tests/integration/test_mysql_protocol/test.py
+++ b/dbms/tests/integration/test_mysql_protocol/test.py
@@ -43,6 +43,13 @@ def golang_container():
     yield docker.from_env().containers.get(cluster.project_name + '_golang1_1')
 
 
+@pytest.fixture(scope='module')
+def php_container():
+    docker_compose = os.path.join(SCRIPT_DIR, 'clients', 'php-mysqlnd', 'docker_compose.yml')
+    subprocess.check_call(['docker-compose', '-p', cluster.project_name, '-f', docker_compose, 'up', '--no-recreate', '-d', '--build'])
+    yield docker.from_env().containers.get(cluster.project_name + '_php1_1')
+
+
 def test_mysql_client(mysql_client, server_address):
     # type: (Container, str) -> None
     code, (stdout, stderr) = mysql_client.exec_run('''
@@ -138,3 +145,10 @@ def test_golang_client(server_address, golang_container):
     with open(os.path.join(SCRIPT_DIR, 'clients', 'golang', '0.reference')) as fp:
         reference = fp.read()
         assert stdout == reference
+
+
+def test_php_client(server_address, php_container):
+    # type: (str, Container) -> None
+    code, (stdout, stderr) = php_container.exec_run('php -f test.php {host} {port} default 123 '.format(host=server_address, port=server_port), demux=True)
+    assert code == 0
+    assert stdout == 'tables\n'
diff --git a/dbms/tests/queries/0_stateless/00029_test_zookeeper_optimize_exception.reference b/dbms/tests/queries/0_stateless/00029_test_zookeeper_optimize_exception.reference
new file mode 100644
index 00000000000..6ed281c757a
--- /dev/null
+++ b/dbms/tests/queries/0_stateless/00029_test_zookeeper_optimize_exception.reference
@@ -0,0 +1,2 @@
+1
+1
diff --git a/dbms/tests/queries/0_stateless/00029_test_zookeeper_optimize_exception.sh b/dbms/tests/queries/0_stateless/00029_test_zookeeper_optimize_exception.sh
new file mode 100755
index 00000000000..ef33f037690
--- /dev/null
+++ b/dbms/tests/queries/0_stateless/00029_test_zookeeper_optimize_exception.sh
@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+
+CUR_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+. $CUR_DIR/../shell_config.sh
+
+
+${CLICKHOUSE_CLIENT} --query="DROP TABLE IF EXISTS test_optimize_exception"
+
+${CLICKHOUSE_CLIENT} --query="CREATE TABLE test_optimize_exception (date Date) ENGINE=MergeTree() PARTITION BY toYYYYMM(date) ORDER BY date"
+${CLICKHOUSE_CLIENT} --query="CREATE TABLE test_optimize_exception_replicated (date Date) ENGINE=ReplicatedMergeTree('/clickhouse/tables/test/optimize', 'r1') PARTITION BY toYYYYMM(date) ORDER BY date"
+
+${CLICKHOUSE_CLIENT} --query="INSERT INTO test_optimize_exception VALUES (toDate('2017-09-09')), (toDate('2017-09-10'))"
+${CLICKHOUSE_CLIENT} --query="INSERT INTO test_optimize_exception VALUES (toDate('2017-09-09')), (toDate('2017-09-10'))"
+${CLICKHOUSE_CLIENT} --query="INSERT INTO test_optimize_exception_replicated VALUES (toDate('2017-09-09')), (toDate('2017-09-10'))"
+${CLICKHOUSE_CLIENT} --query="INSERT INTO test_optimize_exception_replicated VALUES (toDate('2017-09-09')), (toDate('2017-09-10'))"
+
+${CLICKHOUSE_CLIENT} --optimize_throw_if_noop 1 --query="OPTIMIZE TABLE test_optimize_exception PARTITION 201709 FINAL"
+${CLICKHOUSE_CLIENT} --optimize_throw_if_noop 1 --query="OPTIMIZE TABLE test_optimize_exception_replicated PARTITION 201709 FINAL"
+
+echo `${CLICKHOUSE_CLIENT} --optimize_throw_if_noop 1 --server_logs_file=/dev/null --query="OPTIMIZE TABLE test_optimize_exception PARTITION 201710" 2>&1` \
+  | grep -c 'Code: 388. DB::Exception: .* DB::Exception: .* Cannot select parts for optimization'
+echo `${CLICKHOUSE_CLIENT} --optimize_throw_if_noop 1 --server_logs_file=/dev/null --query="OPTIMIZE TABLE test_optimize_exception_replicated PARTITION 201710" 2>&1` \
+  | grep -c 'Code: 388. DB::Exception: .* DB::Exception:.* Cannot select parts for optimization'
diff --git a/dbms/tests/queries/0_stateless/00386_long_in_pk.python b/dbms/tests/queries/0_stateless/00386_long_in_pk.python
index d1db1a32d1e..247e0fe1e61 100644
--- a/dbms/tests/queries/0_stateless/00386_long_in_pk.python
+++ b/dbms/tests/queries/0_stateless/00386_long_in_pk.python
@@ -8,16 +8,16 @@ def gen_queries():
     columns = tuple('a b c d'.split())
     order_by_columns = tuple('a b c'.split())
     partition_by_columns = tuple(' tuple() a'.split())
-    
+
     for partition in partition_by_columns:
         for key_mask in range(1, 1 << len(order_by_columns)):
             key = ','.join(order_by_columns[i] for i in range(len(order_by_columns)) if (1 << i) & key_mask != 0)
             create_query = create_template.format(key, partition)
             for q in (drop_query, create_query, insert_query):
                 yield q
-	    
+
             for column, value in zip(columns, values):
-		yield 'select {} in {} from tab_00386'.format(column, value)
+                yield 'select {} in {} from tab_00386'.format(column, value)
                 yield 'select {} in tuple({}) from tab_00386'.format(column, value)
                 yield 'select {} in (select {} from tab_00386) from tab_00386'.format(column, column)
 
@@ -26,7 +26,7 @@ def gen_queries():
                     yield 'select ({}, {}) in tuple({}, {}) from tab_00386'.format(columns[i], columns[j], values[i], values[j])
                     yield 'select ({}, {}) in (select {}, {} from tab_00386) from tab_00386'.format(columns[i], columns[j], columns[i], columns[j])
                     yield 'select ({}, {}) in (select ({}, {}) from tab_00386) from tab_00386'.format(columns[i], columns[j], columns[i], columns[j])
-            
+
             yield "select e in (1, 'a') from tab_00386"
             yield "select f in tuple((1, 'a')) from tab_00386"
             yield "select f in tuple(tuple((1, 'a'))) from tab_00386"
@@ -41,7 +41,7 @@ import os
 
 def main():
     url = os.environ['CLICKHOUSE_URL_PARAMS']
-    
+
     for q in gen_queries():
         resp = requests.post(url, data=q)
         if resp.status_code != 200 or resp.text.strip() not in ('1', ''):
diff --git a/dbms/tests/queries/0_stateless/00969_columns_clause.reference b/dbms/tests/queries/0_stateless/00969_columns_clause.reference
new file mode 100644
index 00000000000..125a49fae0d
--- /dev/null
+++ b/dbms/tests/queries/0_stateless/00969_columns_clause.reference
@@ -0,0 +1,24 @@
+100	10
+120	8
+0	0
+1	1
+0	0
+1	1
+0
+1
+0
+1
+0
+1
+0
+1
+0
+1
+0
+1
+0
+2
+3
+2
+4
+3
diff --git a/dbms/tests/queries/0_stateless/00969_columns_clause.sql b/dbms/tests/queries/0_stateless/00969_columns_clause.sql
new file mode 100644
index 00000000000..fc5b72d3913
--- /dev/null
+++ b/dbms/tests/queries/0_stateless/00969_columns_clause.sql
@@ -0,0 +1,27 @@
+DROP TABLE IF EXISTS ColumnsClauseTest;
+
+CREATE TABLE ColumnsClauseTest (product_price Int64, product_weight Int16, amount Int64) Engine=TinyLog;
+INSERT INTO ColumnsClauseTest VALUES (100, 10, 324), (120, 8, 23);
+SELECT COLUMNS('product.*') from ColumnsClauseTest ORDER BY product_price;
+
+DROP TABLE ColumnsClauseTest;
+
+SELECT number, COLUMNS('') FROM numbers(2);
+SELECT number, COLUMNS('ber') FROM numbers(2); -- It works for unanchored regular expressions.
+SELECT number, COLUMNS('x') FROM numbers(2);
+SELECT COLUMNS('') FROM numbers(2);
+
+SELECT COLUMNS('x') FROM numbers(10) WHERE number > 5; -- { serverError 51 }
+
+SELECT * FROM numbers(2) WHERE NOT ignore();
+SELECT * FROM numbers(2) WHERE NOT ignore(*);
+SELECT * FROM numbers(2) WHERE NOT ignore(COLUMNS('.+'));
+SELECT * FROM numbers(2) WHERE NOT ignore(COLUMNS('x'));
+SELECT COLUMNS('n') + COLUMNS('u') FROM system.numbers LIMIT 2;
+
+SELECT COLUMNS('n') + COLUMNS('u') FROM (SELECT 1 AS a, 2 AS b); -- { serverError 42 }
+SELECT COLUMNS('a') + COLUMNS('b') FROM (SELECT 1 AS a, 2 AS b);
+SELECT COLUMNS('a') + COLUMNS('a') FROM (SELECT 1 AS a, 2 AS b);
+SELECT COLUMNS('b') + COLUMNS('b') FROM (SELECT 1 AS a, 2 AS b);
+SELECT COLUMNS('a|b') + COLUMNS('b') FROM (SELECT 1 AS a, 2 AS b); -- { serverError 42 }
+SELECT plus(COLUMNS('^(a|b)$')) FROM (SELECT 1 AS a, 2 AS b);
diff --git a/docs/en/operations/table_engines/mergetree.md b/docs/en/operations/table_engines/mergetree.md
index 523b442319a..8610397be7c 100644
--- a/docs/en/operations/table_engines/mergetree.md
+++ b/docs/en/operations/table_engines/mergetree.md
@@ -72,7 +72,7 @@ For a description of request parameters, see [request description](../../query_l
     It must depends on `Date` or `DateTime` column and has one `Date` or `DateTime` column as a result. Example:
     `TTL date + INTERVAL 1 DAY`
 
-    For more details, see [TTL for columns and tables](mergetree.md)
+    For more details, see [TTL for columns and tables](#table_engine-mergetree-ttl)
 
 - `SETTINGS` — Additional parameters that control the behavior of the `MergeTree`:
     - `index_granularity` — The granularity of an index. The number of data rows between the "marks" of an index. By default, 8192. The list of all available parameters you can see in [MergeTreeSettings.h](https://github.com/yandex/ClickHouse/blob/master/dbms/src/Storages/MergeTree/MergeTreeSettings.h).