SHOW STATS_TOPN
May 23, 2024 ยท View on GitHub
The SHOW STATS_TOPN statement shows the Top-N information in statistics.
Currently, the SHOW STATS_TOPN 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 |
Value | The value of this column |
Count | How many times the value appears |
Synopsis
ShowStatsTopnStmt ::=
"SHOW" "STATS_TOPN" ShowLikeOrWhere?
ShowLikeOrWhere ::=
"LIKE" SimpleExpr
| "WHERE" Expression
Example
SHOW STATS_TOPN WHERE Table_name='t';
+---------+------------+----------------+-------------+----------+--------------------------+-------+
| Db_name | Table_name | Partition_name | Column_name | Is_index | Value | Count |
+---------+------------+----------------+-------------+----------+--------------------------+-------+
| test | t | | a | 0 | 2023-12-27 00:00:00 | 1 |
| test | t | | a | 0 | 2023-12-28 00:00:00 | 1 |
| test | t | | ia | 1 | (NULL, 2) | 1 |
| test | t | | ia | 1 | (NULL, 4) | 1 |
| test | t | | ia | 1 | (2023-12-27 00:00:00, 1) | 1 |
| test | t | | ia | 1 | (2023-12-28 00:00:00, 3) | 1 |
+---------+------------+----------------+-------------+----------+--------------------------+-------+
6 rows in set (0.00 sec)
MySQL compatibility
This statement is a TiDB extension to MySQL syntax.