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_granularityvalue: 8192changed: 0description: How many rows correspond to one primary key value.type: SettingUInt64Row 2:──────name: min_bytes_for_wide_partvalue: 0changed: 0description: Minimal uncompressed size in bytes to create part in wide format instead of compacttype: SettingUInt64Row 3:──────name: min_rows_for_wide_partvalue: 0changed: 0description: Minimal number of rows to create part in wide format instead of compacttype: SettingUInt64Row 4:──────name: merge_max_block_sizevalue: 8192changed: 0description: How many rows in blocks should be formed for merge operations.type: SettingUInt644 rows in set. Elapsed: 0.001 sec.
