如何在单个 MySQL 查询中按照一个字段对数据进行排序并分组?
为此,我们首先创建一个表 -
mysql> create table DemoTable ( Message text ); Query OK, 0 rows affected (1.15 sec)
使用插入命令在表中插入一些记录 -
mysql> insert into DemoTable values('Good'); Query OK, 1 row affected (0.43 sec) mysql> insert into DemoTable values('Bye'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values('Awesome'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Bye'); Query OK, 1 row affected (0.08 sec) mysql> insert into DemoTable values('Good'); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable values('Amazing'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('Awesome'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values('Bye'); Query OK, 1 row affected (0.12 sec)
使用 select 语句从表中显示所有记录 -
mysql> select *from DemoTable;
这将产生以下输出 -
+---------+ | Message | +---------+ | Good | | Bye | | Awesome | | Bye | | Good | | Amazing | | Awesome | | Bye | +---------+ 8 rows in set (0.00 sec)
以下是在单个 MySQL 查询中通过 FIELD 对数据进行分组并排序的查询 -
mysql> select *from DemoTable group by Message order by field(Message,'Amazing','Awesome','Good','Bye');
这将产生以下输出 -
+---------+ | Message | +---------+ | Amazing | | Awesome | | Good | | Bye | +---------+ 4 rows in set (0.04 sec)
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