ClickHouse/docs/zh/sql-reference/statements/truncate.md

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---
toc_priority: 52
toc_title: TRUNCATE
---
# TRUNCATE Statement {#truncate-statement}
``` sql
TRUNCATE TABLE [IF EXISTS] [db.]name [ON CLUSTER cluster]
```
Removes all data from a table. When the clause `IF EXISTS` is omitted, the query returns an error if the table does not exist.
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.
You can use the [replication_alter_partitions_sync](../../operations/settings/settings.md#replication-alter-partitions-sync) setting to set up waiting for actions to be executed on replicas.
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.
!!! info "Note"
If the `replication_alter_partitions_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.