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61 lines
1.4 KiB
Markdown
61 lines
1.4 KiB
Markdown
---
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toc_priority: 38
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toc_title: SETTING
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---
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# Table Settings Manipulations {#table_settings_manipulations}
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There is a set of queries to change table settings. You can modify settings or reset them to default values. A single query can change several settings at once.
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If a setting with the specified name does not exist, then the query raises an exception.
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**Syntax**
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``` sql
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ALTER TABLE [db].name [ON CLUSTER cluster] MODIFY|RESET SETTING ...
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```
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!!! note "Note"
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These queries can be applied to [MergeTree](../../../engines/table-engines/mergetree-family/mergetree.md) tables only.
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## MODIFY SETTING {#alter_modify_setting}
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Changes table settings.
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**Syntax**
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```sql
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MODIFY SETTING setting_name=value [, ...]
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```
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**Example**
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```sql
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CREATE TABLE example_table (id UInt32, data String) ENGINE=MergeTree() ORDER BY id;
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ALTER TABLE example_table MODIFY SETTING max_part_loading_threads=8, max_parts_in_total=50000;
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```
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## RESET SETTING {#alter_reset_setting}
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Resets table settings to their default values. If a setting is in a default state, then no action is taken.
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**Syntax**
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```sql
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RESET SETTING setting_name [, ...]
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```
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**Example**
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```sql
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CREATE TABLE example_table (id UInt32, data String) ENGINE=MergeTree() ORDER BY id
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SETTINGS max_part_loading_threads=8;
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ALTER TABLE example_table RESET SETTING max_part_loading_threads;
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```
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**See Also**
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- [MergeTree settings](../../../operations/settings/merge-tree-settings.md)
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