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86 lines
1.6 KiB
Markdown
86 lines
1.6 KiB
Markdown
---
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slug: /en/sql-reference/statements/undrop
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sidebar_label: UNDROP
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---
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# UNDROP TABLE
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Cancels the dropping of the table.
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Beginning with ClickHouse version 23.3 it is possible to UNDROP a table in an Atomic database
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within `database_atomic_delay_before_drop_table_sec` (8 minutes by default) of issuing the DROP TABLE statement. Dropped tables are listed in
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a system table called `system.dropped_tables`.
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If you have a materialized view without a `TO` clause associated with the dropped table, then you will also have to UNDROP the inner table of that view.
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:::tip
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Also see [DROP TABLE](/docs/en/sql-reference/statements/drop.md)
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:::
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Syntax:
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``` sql
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UNDROP TABLE [db.]name [UUID '<uuid>'] [ON CLUSTER cluster]
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```
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**Example**
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```sql
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CREATE TABLE tab
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(
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`id` UInt8
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)
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ENGINE = MergeTree
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ORDER BY id;
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DROP TABLE tab;
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SELECT *
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FROM system.dropped_tables
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FORMAT Vertical;
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```
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```response
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Row 1:
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──────
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index: 0
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database: default
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table: tab
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uuid: aa696a1a-1d70-4e60-a841-4c80827706cc
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engine: MergeTree
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metadata_dropped_path: /var/lib/clickhouse/metadata_dropped/default.tab.aa696a1a-1d70-4e60-a841-4c80827706cc.sql
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table_dropped_time: 2023-04-05 14:12:12
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1 row in set. Elapsed: 0.001 sec.
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```
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```sql
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UNDROP TABLE tab;
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SELECT *
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FROM system.dropped_tables
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FORMAT Vertical;
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```response
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Ok.
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0 rows in set. Elapsed: 0.001 sec.
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```
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```sql
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DESCRIBE TABLE tab
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FORMAT Vertical;
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```
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```response
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Row 1:
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──────
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name: id
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type: UInt8
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default_type:
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default_expression:
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comment:
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codec_expression:
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ttl_expression:
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```
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