在MySQL中列必须满足多个值时如何选择行？
为此，您可以将GROUPBYHAVING子句与一起使用IN()。让我们首先创建一个表-
mysql> create table DemoTable1885 ( FirstName varchar(20), Subject varchar(50) );
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable1885 values('John','MySQL');
mysql> insert into DemoTable1885 values('John','MongoDB');
mysql> insert into DemoTable1885 values('Carol','MySQL');
mysql> insert into DemoTable1885 values('David','Java');使用插入命令在表中显示一些记录-
mysql> select * from DemoTable1885;
这将产生以下输出-
+-----------+---------+ | FirstName | Subject | +-----------+---------+ | John | MySQL| | John | MongoDB| | Carol | MySQL| | David | Java | +-----------+---------+ 4 rows in set (0.00 sec)
这是当列必须满足多个值时选择行的查询：
mysql> select FirstName from DemoTable1885
where Subject IN('MySQL','MongoDB')
group by FirstName
having count(*)=2;这将产生以下输出-
+-----------+ | FirstName | +-----------+ | John | +-----------+ 1 row in set (0.00 sec)