mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-13 09:52:38 +00:00
56 lines
1.4 KiB
Markdown
56 lines
1.4 KiB
Markdown
# system.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**
|
|
```sql
|
|
:) SELECT * FROM system.merge_tree_settings LIMIT 4 FORMAT Vertical;
|
|
```
|
|
|
|
```text
|
|
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.
|
|
```
|
|
|
|
[原文](https://clickhouse.com/docs/zh/operations/system-tables/merge_tree_settings) <!--hide-->
|