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sql-statement-admin-checksum-table.md

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ADMIN CHECKSUM TABLE | TiDB SQL Statement Reference
An overview of the usage of ADMIN for the TiDB database.
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ADMIN CHECKSUM TABLE

The ADMIN CHECKSUM TABLE statement calculates a CRC64 checksum for the data and indexes of a table. This statement is used by programs such as TiDB Lightning to ensure that import operations have completed successfully.

Synopsis

AdminStmt ::=
    'ADMIN' ( 'SHOW' ( 'DDL' ( 'JOBS' Int64Num? WhereClauseOptional | 'JOB' 'QUERIES' NumList )? | TableName 'NEXT_ROW_ID' | 'SLOW' AdminShowSlow ) | 'CHECK' ( 'TABLE' TableNameList | 'INDEX' TableName Identifier ( HandleRange ( ',' HandleRange )* )? ) | 'RECOVER' 'INDEX' TableName Identifier | 'CLEANUP' ( 'INDEX' TableName Identifier | 'TABLE' 'LOCK' TableNameList ) | 'CHECKSUM' 'TABLE' TableNameList | 'CANCEL' 'DDL' 'JOBS' NumList | 'RELOAD' ( 'EXPR_PUSHDOWN_BLACKLIST' | 'OPT_RULE_BLACKLIST' | 'BINDINGS' ) | 'PLUGINS' ( 'ENABLE' | 'DISABLE' ) PluginNameList | 'REPAIR' 'TABLE' TableName CreateTableStmt | ( 'FLUSH' | 'CAPTURE' | 'EVOLVE' ) 'BINDINGS' )

TableNameList ::=
    TableName ( ',' TableName )*

Examples

Calculate the checksum for a table:

{{< copyable "sql" >}}

CREATE TABLE t1 (id INT NOT NULL PRIMARY KEY auto_increment);
INSERT INTO t1 VALUES (1),(2),(3);
ADMIN CHECKSUM TABLE t1;
mysql> CREATE TABLE t1 (id INT NOT NULL PRIMARY KEY auto_increment);
Query OK, 0 rows affected (0.11 sec)

mysql> INSERT INTO t1 VALUES (1),(2),(3);
Query OK, 3 rows affected (0.02 sec)
Records: 3  Duplicates: 0  Warnings: 0

mysql> ADMIN CHECKSUM TABLE t1;
+---------+------------+----------------------+-----------+-------------+
| Db_name | Table_name | Checksum_crc64_xor   | Total_kvs | Total_bytes |
+---------+------------+----------------------+-----------+-------------+
| test    | t1         | 10909174369497628533 |         3 |          75 |
+---------+------------+----------------------+-----------+-------------+
1 row in set (0.00 sec)

MySQL compatibility

This statement is a TiDB extension to MySQL syntax.