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  • mysql 分组和排序

    mysql> select * from table1;
    +----------+------------+-----+---------------------+
    | name_new | transactor | pid | order_date          |
    +----------+------------+-----+---------------------+
    | 1hahha   | 1xiaohong  |   1 | 2019-08-04 20:45:47 |
    | 2hahha   | 2xiaohong  |   2 | 2019-08-04 20:45:57 |
    | 3hahha   | 3xiaohong  |   3 | 2019-08-04 20:46:02 |
    | 4hahha   | 4xiaohong  |   4 | 2019-08-04 20:46:05 |
    | 3hahha   | bob        |   5 | 2019-08-04 20:46:08 |
    | 3hahha   | lee        |   6 | 2019-08-04 20:46:12 |
    | 3hahha   | lee        |   7 | 2019-08-04 21:56:01 |
    | 3hahha   | lee        |   8 | 2019-08-04 21:56:10 |
    | 3hahha   | bob        |   9 | 2019-08-04 21:56:18 |
    | 3hahha   | bob        |  10 | 2019-08-04 21:56:26 |
    +----------+------------+-----+---------------------+
    10 rows in set (0.00 sec)
    
    
    mysql> select transactor,count(*) as num from table1 where pid >=4 group by transactor;
    +------------+-----+
    | transactor | num |
    +------------+-----+
    | 4xiaohong  |   1 |
    | bob        |   3 |
    | lee        |   3 |
    +------------+-----+
    3 rows in set (0.00 sec)
    
    
    mysql> select transactor,count(*) as num from table1 where pid >=4 group by transactor with rollup;
    +------------+-----+
    | transactor | num |
    +------------+-----+
    | 4xiaohong  |   1 |
    | bob        |   3 |
    | lee        |   3 |
    | NULL       |   7 |
    +------------+-----+
    4 rows in set (0.00 sec)
    
    
    mysql> select transactor,count(*) as num from table1 where pid >=4 group by transactor with rollup having num>=3 order by transactor;
    ERROR 1221 (HY000): Incorrect usage of CUBE/ROLLUP and ORDER BY
    
    
    mysql> select transactor,count(*) as num from table1 where pid >=4 group by transactor having num>=3 order by transactor;
    +------------+-----+
    | transactor | num |
    +------------+-----+
    | bob        |   3 |
    | lee        |   3 |
    +------------+-----+
    2 rows in set (0.00 sec)
    
    
    mysql> select transactor,count(*) as num from table1 where pid >=4 group by transactor having num>=3 order by transactor desc;
    +------------+-----+
    | transactor | num |
    +------------+-----+
    | lee        |   3 |
    | bob        |   3 |
    +------------+-----+
    2 rows in set (0.00 sec)

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  • 原文地址:https://www.cnblogs.com/sea-stream/p/11300308.html
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