UNDROP TABLE

Cancels the dropping of the table.

Beginning with ClickHouse version 23.3, you can recover a table in an Atomic database with UNDROP TABLE during the period set by database_atomic_delay_before_drop_table_sec (8 minutes by default) after issuing DROP TABLE. Tables dropped from Atomic databases are listed in system.dropped_tables.

For a Shared database in ClickHouse Cloud, this period is instead controlled by database_shared_drop_table_delay_seconds, which defaults to 8 hours. Tables dropped from Shared databases aren't listed in system.dropped_tables.

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.

Tip

Also see DROP TABLE

Syntax:

UNDROP TABLE [db.]name [UUID '<uuid>'] [ON CLUSTER cluster]

Example

CREATE TABLE tab
(
    `id` UInt8
)
ENGINE = MergeTree
ORDER BY id;

DROP TABLE tab;

SELECT *
FROM system.dropped_tables
FORMAT Vertical;

Row 1:
──────
index:                 0
database:              default
table:                 tab
uuid:                  aa696a1a-1d70-4e60-a841-4c80827706cc
engine:                MergeTree
metadata_dropped_path: /var/lib/clickhouse/metadata_dropped/default.tab.aa696a1a-1d70-4e60-a841-4c80827706cc.sql
table_dropped_time:    2023-04-05 14:12:12

1 row in set. Elapsed: 0.001 sec. 

UNDROP TABLE tab;

SELECT *
FROM system.dropped_tables
FORMAT Vertical;

```response
Ok.

0 rows in set. Elapsed: 0.001 sec. 

DESCRIBE TABLE tab
FORMAT Vertical;

Row 1:
──────
name:               id
type:               UInt8
default_type:       
default_expression: 
comment:            
codec_expression:   
ttl_expression: