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1.4 KiB
1.4 KiB
slug |
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/zh/operations/system-tables/merge_tree_settings |
system.merge_tree_settings
包含 MergeTree
表的设置 (Setting) 信息。
列:
name
(String) — 设置名称。value
(String) — 设置的值。description
(String) — 设置描述。type
(String) — 设置类型 (执行特定的字符串值)。changed
(UInt8) — 该设置是否在配置中明确定义或是明确改变。
示例
SELECT * FROM system.merge_tree_settings LIMIT 4 FORMAT Vertical;
Row 1:
──────
name: index_granularity
value: 8192
changed: 0
description: How many rows correspond to one primary key value.
type: SettingUInt64
Row 2:
──────
name: min_bytes_for_wide_part
value: 0
changed: 0
description: Minimal uncompressed size in bytes to create part in wide format instead of compact
type: SettingUInt64
Row 3:
──────
name: min_rows_for_wide_part
value: 0
changed: 0
description: Minimal number of rows to create part in wide format instead of compact
type: SettingUInt64
Row 4:
──────
name: merge_max_block_size
value: 8192
changed: 0
description: How many rows in blocks should be formed for merge operations.
type: SettingUInt64
4 rows in set. Elapsed: 0.001 sec.