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

SHOW STATS_BUCKETS

The SHOW STATS_BUCKETS statement shows the bucket information in statistics.

Currently, the SHOW STATS_BUCKETS 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 (when is_index is 0) or the index name (when is_index is 1)
Is_index Whether it is an index column or not
Bucket_id The ID of a bucket
Count The number of all the values that falls on the bucket and the previous buckets
Repeats The occurrence number of the maximum value
Lower_bound The minimum value
Upper_bound The maximum value
Ndv The number of distinct values in the bucket. This field is deprecated and always shows 0 due to its inaccurate value.

Synopsis

ShowStatsBucketsStmt ::=
    "SHOW" "STATS_BUCKETS" ShowLikeOrWhere?

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

Examples

SHOW STATS_BUCKETS WHERE Table_name='t';
+---------+------------+----------------+-------------+----------+-----------+-------+---------+--------------------------+--------------------------+------+
| Db_name | Table_name | Partition_name | Column_name | Is_index | Bucket_id | Count | Repeats | Lower_Bound              | Upper_Bound              | Ndv  |
+---------+------------+----------------+-------------+----------+-----------+-------+---------+--------------------------+--------------------------+------+
| test    | t          |                | a           |        0 |         0 |     1 |       1 | 2023-12-27 00:00:00      | 2023-12-27 00:00:00      |    0 |
| test    | t          |                | a           |        0 |         1 |     2 |       1 | 2023-12-28 00:00:00      | 2023-12-28 00:00:00      |    0 |
| test    | t          |                | ia          |        1 |         0 |     1 |       1 | (NULL, 2)                | (NULL, 2)                |    0 |
| test    | t          |                | ia          |        1 |         1 |     2 |       1 | (NULL, 4)                | (NULL, 4)                |    0 |
| test    | t          |                | ia          |        1 |         2 |     3 |       1 | (2023-12-27 00:00:00, 1) | (2023-12-27 00:00:00, 1) |    0 |
| test    | t          |                | ia          |        1 |         3 |     4 |       1 | (2023-12-28 00:00:00, 3) | (2023-12-28 00:00:00, 3) |    0 |
+---------+------------+----------------+-------------+----------+-----------+-------+---------+--------------------------+--------------------------+------+
6 rows in set (0.00 sec)

MySQL compatibility

This statement is a TiDB extension to MySQL syntax.

See also