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56 lines
1.4 KiB
Markdown
56 lines
1.4 KiB
Markdown
---
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slug: /en/operations/system-tables/merge_tree_settings
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title: merge_tree_settings
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---
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Contains information about settings for `MergeTree` tables.
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Columns:
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- `name` (String) — Setting name.
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- `value` (String) — Setting value.
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- `description` (String) — Setting description.
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- `type` (String) — Setting type (implementation specific string value).
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- `changed` (UInt8) — Whether the setting was explicitly defined in the config or explicitly changed.
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**Example**
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```sql
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:) SELECT * FROM system.merge_tree_settings LIMIT 4 FORMAT Vertical;
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```
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```text
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Row 1:
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──────
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name: index_granularity
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value: 8192
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changed: 0
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description: How many rows correspond to one primary key value.
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type: SettingUInt64
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Row 2:
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──────
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name: min_bytes_for_wide_part
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value: 0
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changed: 0
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description: Minimal uncompressed size in bytes to create part in wide format instead of compact
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type: SettingUInt64
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Row 3:
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──────
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name: min_rows_for_wide_part
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value: 0
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changed: 0
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description: Minimal number of rows to create part in wide format instead of compact
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type: SettingUInt64
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Row 4:
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──────
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name: merge_max_block_size
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value: 8192
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changed: 0
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description: How many rows in blocks should be formed for merge operations.
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type: SettingUInt64
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4 rows in set. Elapsed: 0.001 sec.
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```
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