SHOW-QUERY-STATS

Name

SHOW QUERY STATS

Description

该语句用于展示数据库中历史查询命中的库表列的情况

SHOW QUERY STATS [[FOR db_name]|[FROM table_name]] [ALL] [VERBOSE]];

说明：

1. 支持查询数据库和表的历史查询命中情况，重启 fe 后数据会重置，每个 fe 单独统计
2. 通过 FOR DATABASE 和 FROM TABLE 可以指定查询数据库或者表的命中情况，后面分别接数据库名或者表名
3. ALL 可以指定是否展示所有 index 的查询命中情况，VERBOSE 可以展示更详细的命中情况，这两个参数可以单独使用， 也可以一起使用，但是必须放在最后 而且只能用在表的查询上
4. 如果没有 use 任何数据库那么直接执行SHOW QUERY STATS 将展示所有数据库的命中情况
5. 命中结果中可能有两列： QueryCount：该列被查询次数 FilterCount: 该列作为 where 条件被查询的次数

Example

1. 展示表baseall 的查询命中情况

    MySQL [test_query_db]> show query stats from baseall;
    +-------+------------+-------------+
    | Field | QueryCount | FilterCount |
    +-------+------------+-------------+
    | k0    | 0          | 0           |
    | k1    | 0          | 0           |
    | k2    | 0          | 0           |
    | k3    | 0          | 0           |
    | k4    | 0          | 0           |
    | k5    | 0          | 0           |
    | k6    | 0          | 0           |
    | k10   | 0          | 0           |
    | k11   | 0          | 0           |
    | k7    | 0          | 0           |
    | k8    | 0          | 0           |
    | k9    | 0          | 0           |
    | k12   | 0          | 0           |
    | k13   | 0          | 0           |
    +-------+------------+-------------+
    14 rows in set (0.002 sec)
    
    MySQL [test_query_db]> select k0, k1,k2, sum(k3) from baseall  where k9 > 1 group by k0,k1,k2;
    +------+------+--------+-------------+
    | k0   | k1   | k2     | sum(`k3`)   |
    +------+------+--------+-------------+
    |    0 |    6 |  32767 |        3021 |
    |    1 |   12 |  32767 | -2147483647 |
    |    0 |    3 |   1989 |        1002 |
    |    0 |    7 | -32767 |        1002 |
    |    1 |    8 |    255 |  2147483647 |
    |    1 |    9 |   1991 | -2147483647 |
    |    1 |   11 |   1989 |       25699 |
    |    1 |   13 | -32767 |  2147483647 |
    |    1 |   14 |    255 |         103 |
    |    0 |    1 |   1989 |        1001 |
    |    0 |    2 |   1986 |        1001 |
    |    1 |   15 |   1992 |        3021 |
    +------+------+--------+-------------+
    12 rows in set (0.050 sec)
    
    MySQL [test_query_db]> show query stats from baseall;
    +-------+------------+-------------+
    | Field | QueryCount | FilterCount |
    +-------+------------+-------------+
    | k0    | 1          | 0           |
    | k1    | 1          | 0           |
    | k2    | 1          | 0           |
    | k3    | 1          | 0           |
    | k4    | 0          | 0           |
    | k5    | 0          | 0           |
    | k6    | 0          | 0           |
    | k10   | 0          | 0           |
    | k11   | 0          | 0           |
    | k7    | 0          | 0           |
    | k8    | 0          | 0           |
    | k9    | 1          | 1           |
    | k12   | 0          | 0           |
    | k13   | 0          | 0           |
    +-------+------------+-------------+
    14 rows in set (0.001 sec)

2. 展示表的所物化视图的的命中的汇总情况

   MySQL [test_query_db]> show query stats from baseall all;
    +-----------+------------+
    | IndexName | QueryCount |
    +-----------+------------+
    | baseall   | 1          |
    +-----------+------------+
    1 row in set (0.005 sec)

3. 展示表的所物化视图的的命中的详细情况

    MySQL [test_query_db]> show query stats from baseall all verbose;
    +-----------+-------+------------+-------------+
    | IndexName | Field | QueryCount | FilterCount |
    +-----------+-------+------------+-------------+
    | baseall   | k0    | 1          | 0           |
    |           | k1    | 1          | 0           |
    |           | k2    | 1          | 0           |
    |           | k3    | 1          | 0           |
    |           | k4    | 0          | 0           |
    |           | k5    | 0          | 0           |
    |           | k6    | 0          | 0           |
    |           | k10   | 0          | 0           |
    |           | k11   | 0          | 0           |
    |           | k7    | 0          | 0           |
    |           | k8    | 0          | 0           |
    |           | k9    | 1          | 1           |
    |           | k12   | 0          | 0           |
    |           | k13   | 0          | 0           |
    +-----------+-------+------------+-------------+
    14 rows in set (0.017 sec)

4. 展示数据库的命中情况

    MySQL [test_query_db]> show query stats for test_query_db;
    +----------------------------+------------+
    | TableName                  | QueryCount |
    +----------------------------+------------+
    | compaction_tbl             | 0          |
    | bigtable                   | 0          |
    | empty                      | 0          |
    | tempbaseall                | 0          |
    | test                       | 0          |
    | test_data_type             | 0          |
    | test_string_function_field | 0          |
    | baseall                    | 1          |
    | nullable                   | 0          |
    +----------------------------+------------+
    9 rows in set (0.005 sec)

5. 展示所有数据库的命中情况，这时不能 use 任何数据库

    MySQL [(none)]> show query stats;
    +-----------------+------------+
    | Database        | QueryCount |
    +-----------------+------------+
    | test_query_db   | 1          |
    +-----------------+------------+
    1 rows in set (0.005 sec)

   SHOW QUERY STATS;

Keywords

 SHOW， QUERY, STATS;

Best Practice