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Signed-off-by: Duc Canh Le <duccanh.le@ahrefs.com>
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Duc Canh Le 2024-01-05 07:13:46 +00:00
parent 29c4d96b48
commit 934e006213
2 changed files with 19 additions and 1 deletions
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18
docs/en/operations/settings/settings.md
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@ -4771,6 +4771,24 @@ Type: Int64
Default: 0
## output_format_compression_level
Default compression level if query output is compressed. The setting is applied when `SELECT` query has `INTO OUTFILE` or when inserting to table fuction `file`, `url`, `hdfs`, `s3`, and `azureBlobStorage`.
Possible values: from `1` to `22`
Default: `3`
## output_format_compression_zstd_window_log
To be used when `output_format_compression_level` is `zstd`. If greater than `0`, this setting explicitly sets compression window size (expressed as power of `2`) and enable long-range mode for zstd compression. This can help to achive better compression ratio.
Possible values: non-negative numbers. Note that if the value is too small or too big, `zstdlib` will throw exception. Typical values are from `20` (window size = `1MB`) to `30` (window size = `1GB`).
Default: `0`
## rewrite_count_distinct_if_with_count_distinct_implementation
Allows you to rewrite `countDistcintIf` with [count_distinct_implementation](#count_distinct_implementation) setting.

2
src/Core/Settings.h
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@ -204,7 +204,7 @@ class IColumn;
M(Bool, input_format_parallel_parsing, true, "Enable parallel parsing for some data formats.", 0) \
M(UInt64, min_chunk_bytes_for_parallel_parsing, (10 * 1024 * 1024), "The minimum chunk size in bytes, which each thread will parse in parallel.", 0) \
M(Bool, output_format_parallel_formatting, true, "Enable parallel formatting for some data formats.", 0) \
M(UInt64, output_format_compression_level, 3, "Default compression level if output is compressed", 0) \
M(UInt64, output_format_compression_level, 3, "Default compression level if query output is compressed. The setting is applied when `SELECT` query has `INTO OUTFILE` or when inserting to table fuction `file`, `url`, `hdfs`, `s3`, and `azureBlobStorage`", 0) \
M(UInt64, output_format_compression_zstd_window_log, 0, "If > 0, explicitly set window size and enable long-range mode for zstd compression, expressed as power of 2", 0) \
\
M(UInt64, merge_tree_min_rows_for_concurrent_read, (20 * 8192), "If at least as many lines are read from one file, the reading can be parallelized.", 0) \