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32 lines
1.5 KiB
Markdown
32 lines
1.5 KiB
Markdown
---
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slug: /en/sql-reference/statements/truncate
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sidebar_position: 52
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sidebar_label: TRUNCATE
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---
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# TRUNCATE Statements
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## TRUNCATE TABLE
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``` sql
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TRUNCATE TABLE [IF EXISTS] [db.]name [ON CLUSTER cluster]
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```
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Removes all data from a table. When the clause `IF EXISTS` is omitted, the query returns an error if the table does not exist.
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The `TRUNCATE` query is not supported for [View](../../engines/table-engines/special/view.md), [File](../../engines/table-engines/special/file.md), [URL](../../engines/table-engines/special/url.md), [Buffer](../../engines/table-engines/special/buffer.md) and [Null](../../engines/table-engines/special/null.md) table engines.
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You can use the [alter_sync](../../operations/settings/settings.md#alter-sync) setting to set up waiting for actions to be executed on replicas.
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You can specify how long (in seconds) to wait for inactive replicas to execute `TRUNCATE` queries with the [replication_wait_for_inactive_replica_timeout](../../operations/settings/settings.md#replication-wait-for-inactive-replica-timeout) setting.
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:::note
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If the `alter_sync` is set to `2` and some replicas are not active for more than the time, specified by the `replication_wait_for_inactive_replica_timeout` setting, then an exception `UNFINISHED` is thrown.
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:::
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## TRUNCATE DATABASE
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``` sql
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TRUNCATE DATABASE [IF EXISTS] [db.]name [ON CLUSTER cluster]
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```
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Removes all tables from a database but keeps the database itself. When the clause `IF EXISTS` is omitted, the query returns an error if the database does not exist.
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