Merge pull request #38907 from evillique/compression_level

Add compression level for data export

docs/en/sql-reference/statements/select/index.md

@@ -25,7 +25,7 @@ SELECT [DISTINCT [ON (column1, column2, ...)]] expr_list
 [LIMIT [n, ]m] [WITH TIES]
 [SETTINGS ...]
 [UNION  ...]
-[INTO OUTFILE filename [COMPRESSION type] ]
+[INTO OUTFILE filename [COMPRESSION type [LEVEL level]] ]
 [FORMAT format]
 ```
 

docs/en/sql-reference/statements/select/into-outfile.md

@@ -6,16 +6,18 @@ sidebar_label: INTO OUTFILE
 
 `INTO OUTFILE` clause redirects the result of a `SELECT` query to a file on the **client** side.
 
-Compressed files are supported. Compression type is detected by the extension of the file name (mode `'auto'` is used by default). Or it can be explicitly specified in a `COMPRESSION` clause.
+Compressed files are supported. Compression type is detected by the extension of the file name (mode `'auto'` is used by default). Or it can be explicitly specified in a `COMPRESSION` clause. The compression level for a certain compression type can be specified in a `LEVEL` clause.
 
 **Syntax**
 
 ```sql
-SELECT <expr_list> INTO OUTFILE file_name [COMPRESSION type]
+SELECT <expr_list> INTO OUTFILE file_name [COMPRESSION type [LEVEL level]]
 ```
 
 `file_name` and `type` are string literals. Supported compression types are: `'none'`, `'gzip'`, `'deflate'`, `'br'`, `'xz'`, `'zstd'`, `'lz4'`, `'bz2'`.
 
+`level` is a numeric literal. Positive integers in following ranges are supported: `1-12` for `lz4` type, `1-22` for `zstd` type and `1-9` for other compression types.
+
 ## Implementation Details
 
 -   This functionality is available in the [command-line client](../../../interfaces/cli.md) and [clickhouse-local](../../../operations/utilities/clickhouse-local.md). Thus a query sent via [HTTP interface](../../../interfaces/http.md) will fail.

docs/ru/sql-reference/statements/select/index.md

@@ -24,7 +24,7 @@ SELECT [DISTINCT [ON (column1, column2, ...)]] expr_list
 [LIMIT [n, ]m] [WITH TIES]
 [SETTINGS ...]
 [UNION ALL ...]
-[INTO OUTFILE filename [COMPRESSION type] ]
+[INTO OUTFILE filename [COMPRESSION type [LEVEL level]] ]
 [FORMAT format]
 ```
 

docs/ru/sql-reference/statements/select/into-outfile.md

@@ -6,16 +6,18 @@ sidebar_label: INTO OUTFILE
 
 Секция `INTO OUTFILE` перенаправляет результат запроса `SELECT` в файл на стороне **клиента**.
 
-Поддерживаются сжатые файлы. Формат сжатия определяется по расширению файла (по умолчанию используется режим `'auto'`), либо он может быть задан явно в секции `COMPRESSION`. 
+Поддерживаются сжатые файлы. Формат сжатия определяется по расширению файла (по умолчанию используется режим `'auto'`), либо он может быть задан явно в секции `COMPRESSION`. Уровень сжатия для конкретного алгоритма может быть задан в секции `LEVEL`.
 
 **Синтаксис**
 
 ```sql
-SELECT <expr_list> INTO OUTFILE file_name [COMPRESSION type]
+SELECT <expr_list> INTO OUTFILE file_name [COMPRESSION type [LEVEL level]]
 ```
 
 `file_name` и `type` задаются в виде строковых литералов. Поддерживаются форматы сжатия: `'none`', `'gzip'`, `'deflate'`, `'br'`, `'xz'`, `'zstd'`, `'lz4'`, `'bz2'`.
 
+`level` задается в виде числового литерала. Поддерживаются положительные значения в следующих диапазонах: `1-12` для формата `lz4`, `1-22` для формата `zstd` и `1-9` для остальных форматов.
+
 ## Детали реализации {#implementation-details}
 
 -   Эта функция доступна только в следующих интерфейсах: [клиент командной строки](../../../interfaces/cli.md) и [clickhouse-local](../../../operations/utilities/clickhouse-local.md). Таким образом, запрос, отправленный через [HTTP интерфейс](../../../interfaces/http.md) вернет ошибку.

src/Client/ClientBase.cpp

@@ -524,17 +524,35 @@ try
                 const auto & out_file_node = query_with_output->out_file->as<ASTLiteral &>();
                 out_file = out_file_node.value.safeGet<std::string>();
 
-                std::string compression_method;
+                std::string compression_method_string;
+
                 if (query_with_output->compression)
                 {
                     const auto & compression_method_node = query_with_output->compression->as<ASTLiteral &>();
-                    compression_method = compression_method_node.value.safeGet<std::string>();
+                    compression_method_string = compression_method_node.value.safeGet<std::string>();
+                }
+
+                CompressionMethod compression_method = chooseCompressionMethod(out_file, compression_method_string);
+                UInt64 compression_level = 3;
+
+                if (query_with_output->compression_level)
+                {
+                    const auto & compression_level_node = query_with_output->compression_level->as<ASTLiteral &>();
+                    bool res = compression_level_node.value.tryGet<UInt64>(compression_level);
+                    auto range = getCompressionLevelRange(compression_method);
+
+                    if (!res || compression_level < range.first || compression_level > range.second)
+                        throw Exception(
+                            ErrorCodes::BAD_ARGUMENTS,
+                            "Invalid compression level, must be positive integer in range {}-{}",
+                            range.first,
+                            range.second);
                 }
 
                 out_file_buf = wrapWriteBufferWithCompressionMethod(
                     std::make_unique<WriteBufferFromFile>(out_file, DBMS_DEFAULT_BUFFER_SIZE, O_WRONLY | O_EXCL | O_CREAT),
-                    chooseCompressionMethod(out_file, compression_method),
+                    compression_method,
-                    /* compression level = */ 3
+                    compression_level
                 );
 
                 // We are writing to file, so default format is the same as in non-interactive mode.

src/IO/CompressionMethod.cpp

@@ -98,6 +98,19 @@ CompressionMethod chooseCompressionMethod(const std::string & path, const std::s
         ErrorCodes::NOT_IMPLEMENTED);
 }
 
+std::pair<uint64_t, uint64_t> getCompressionLevelRange(const CompressionMethod & method)
+{
+    switch (method)
+    {
+        case CompressionMethod::Zstd:
+            return {1, 22};
+        case CompressionMethod::Lz4:
+            return {1, 12};
+        default:
+            return {1, 9};
+    }
+}
+
 static std::unique_ptr<CompressedReadBufferWrapper> createCompressedWrapper(
     std::unique_ptr<ReadBuffer> nested, CompressionMethod method, size_t buf_size, char * existing_memory, size_t alignment, int zstd_window_log_max)
 {

src/IO/CompressionMethod.h

@@ -46,6 +46,9 @@ std::string toContentEncodingName(CompressionMethod method);
   */
 CompressionMethod chooseCompressionMethod(const std::string & path, const std::string & hint);
 
+/// Get a range of the valid compression levels for the compression method.
+std::pair<uint64_t, uint64_t> getCompressionLevelRange(const CompressionMethod & method);
+
 std::unique_ptr<ReadBuffer> wrapReadBufferWithCompressionMethod(
     std::unique_ptr<ReadBuffer> nested,
     CompressionMethod method,

src/Parsers/ASTQueryWithOutput.h

@@ -18,6 +18,7 @@ public:
     ASTPtr format;
     ASTPtr settings_ast;
     ASTPtr compression;
+    ASTPtr compression_level;
 
     void formatImpl(const FormatSettings & s, FormatState & state, FormatStateStacked frame) const final;
 

src/Parsers/ParserQueryWithOutput.cpp

@@ -96,6 +96,14 @@ bool ParserQueryWithOutput::parseImpl(Pos & pos, ASTPtr & node, Expected & expec
             ParserStringLiteral compression;
             if (!compression.parse(pos, query_with_output.compression, expected))
                 return false;
+
+            ParserKeyword s_compression_level("LEVEL");
+            if (s_compression_level.ignore(pos, expected))
+            {
+                ParserNumber compression_level;
+                if (!compression_level.parse(pos, query_with_output.compression_level, expected))
+                    return false;
+            }
         }
 
         query_with_output.children.push_back(query_with_output.out_file);

tests/queries/0_stateless/02353_compression_level.reference

@@ -0,0 +1,18 @@
+6000	5999	13
+6000	5999	13
+Ok
+6000	5999	13
+6000	5999	13
+Ok
+6000	5999	13
+6000	5999	13
+Ok
+6000	5999	13
+6000	5999	13
+Ok
+6000	5999	13
+6000	5999	13
+Ok
+6000	5999	13
+6000	5999	13
+Ok

tests/queries/0_stateless/02353_compression_level.sh

@@ -0,0 +1,34 @@
+#!/usr/bin/env bash
+# Tags: no-fasttest, no-parallel
+# Tag no-fasttest: depends on brotli and bzip2
+
+CURDIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+# shellcheck source=../shell_config.sh
+. "$CURDIR"/../shell_config.sh
+
+USER_FILES_PATH=$(clickhouse-client --query "select _path,_file from file('nonexist.txt', 'CSV', 'val1 char')" 2>&1 | grep Exception | awk '{gsub("/nonexist.txt","",$9); print $9}')
+WORKING_FOLDER_02353="${USER_FILES_PATH}/${CLICKHOUSE_DATABASE}"
+
+rm -rf "${WORKING_FOLDER_02353}"
+mkdir "${WORKING_FOLDER_02353}"
+
+for m in gz br xz zst lz4 bz2
+do
+    ${CLICKHOUSE_CLIENT} --query "SELECT number, 'Hello, world!' FROM numbers(6000) INTO OUTFILE '${WORKING_FOLDER_02353}/${m}_1.${m}' COMPRESSION '${m}' LEVEL 1"
+    ${CLICKHOUSE_CLIENT} --query "SELECT number, 'Hello, world!' FROM numbers(6000) INTO OUTFILE '${WORKING_FOLDER_02353}/${m}_9.${m}' COMPRESSION '${m}' LEVEL 9"
+
+    ${CLICKHOUSE_CLIENT} --query "SELECT count(), max(x), avg(length(s)) FROM file('${WORKING_FOLDER_02353}/${m}_1.${m}', 'TabSeparated', 'x UInt32, s String')"
+    ${CLICKHOUSE_CLIENT} --query "SELECT count(), max(x), avg(length(s)) FROM file('${WORKING_FOLDER_02353}/${m}_9.${m}', 'TabSeparated', 'x UInt32, s String')"
+
+    level_1=$(du -b ${WORKING_FOLDER_02353}/${m}_1.${m} | awk '{print $1}')
+    level_9=$(du -b ${WORKING_FOLDER_02353}/${m}_9.${m} | awk '{print $1}')
+
+    if [ "$level_1" != "$level_9" ]; then
+        echo "Ok"
+    else
+        echo "Failed"
+    fi
+
+done
+
+rm -rf "${WORKING_FOLDER_02353}"