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SHOW COLUMN_STATS_USAGE
An overview of the usage of SHOW COLUMN_STATS_USAGE for TiDB database.

SHOW COLUMN_STATS_USAGE

The SHOW COLUMN_STATS_USAGE statement shows the last usage time and collection time of column statistics. You can also use it to locate PREDICATE COLUMNS and columns on which statistics have been collected.

Currently, the SHOW COLUMN_STATS_USAGE statement returns the following columns:

Column name Description
Db_name The database name
Table_name The table name
Partition_name The partition name
Column_name The column name
Last_used_at The last time when the column statistics were used in the query optimization
Last_analyzed_at The last time when the column statistics were collected

Synopsis

ShowColumnStatsUsageStmt ::=
    "SHOW" "COLUMN_STATS_USAGE" ShowLikeOrWhere?

ShowLikeOrWhere ::=
    "LIKE" SimpleExpr
|   "WHERE" Expression

Examples

SHOW COLUMN_STATS_USAGE;
+---------+------------+----------------+-------------+--------------+---------------------+
| Db_name | Table_name | Partition_name | Column_name | Last_used_at | Last_analyzed_at    |
+---------+------------+----------------+-------------+--------------+---------------------+
| test    | t1         |                | id          | NULL         | 2024-05-10 11:04:23 |
| test    | t1         |                | b           | NULL         | 2024-05-10 11:04:23 |
| test    | t1         |                | pad         | NULL         | 2024-05-10 11:04:23 |
| test    | t          |                | a           | NULL         | 2024-05-10 11:37:06 |
| test    | t          |                | b           | NULL         | 2024-05-10 11:37:06 |
+---------+------------+----------------+-------------+--------------+---------------------+
5 rows in set (0.00 sec)

MySQL compatibility

This statement is a TiDB extension to MySQL syntax.

See also