SHOW STATS_HISTOGRAMS
This statement shows the histogram information collected by the ANALYZE
statement as part of database statistics.
Synopsis
- ShowStatsHistogramsStmt
- ShowLikeOrWhere
ShowStatsHistogramsStmt ::=
"SHOW" "STATS_HISTOGRAMS" ShowLikeOrWhere?
ShowLikeOrWhere ::=
"LIKE" SimpleExpr
| "WHERE" Expression
Examples
SHOW STATS_HISTOGRAMS;
+---------+------------+----------------+-------------+----------+---------------------+----------------+------------+--------------+-------------+
| Db_name | Table_name | Partition_name | Column_name | Is_index | Update_time | Distinct_count | Null_count | Avg_col_size | Correlation |
+---------+------------+----------------+-------------+----------+---------------------+----------------+------------+--------------+-------------+
| test | t | | a | 0 | 2020-05-25 19:20:00 | 7 | 0 | 1 | 1 |
| test | t2 | | a | 0 | 2020-05-25 19:20:01 | 6 | 0 | 8 | 0 |
| test | t2 | | b | 0 | 2020-05-25 19:20:01 | 6 | 0 | 1.67 | 1 |
+---------+------------+----------------+-------------+----------+---------------------+----------------+------------+--------------+-------------+
3 rows in set (0.00 sec)
SHOW STATS_HISTOGRAMS WHERE table_name = 't2';
+---------+------------+----------------+-------------+----------+---------------------+----------------+------------+--------------+-------------+
| Db_name | Table_name | Partition_name | Column_name | Is_index | Update_time | Distinct_count | Null_count | Avg_col_size | Correlation |
+---------+------------+----------------+-------------+----------+---------------------+----------------+------------+--------------+-------------+
| test | t2 | | b | 0 | 2020-05-25 19:20:01 | 6 | 0 | 1.67 | 1 |
| test | t2 | | a | 0 | 2020-05-25 19:20:01 | 6 | 0 | 8 | 0 |
+---------+------------+----------------+-------------+----------+---------------------+----------------+------------+--------------+-------------+
2 rows in set (0.00 sec)
MySQL compatibility
This statement is a TiDB extension to MySQL syntax.