删

删除特定条件的数据

DELETE FROM '表名' WHERE '列名=特定值'

DELETE FROM userTable WHERE id=1;

删除所有行

DELETE FROM userTable;

使用子查询删除数据

DELETE FROM '表名' WHERE '列名' IN (SELECT '列名' FROM '另一个表名' WHERE '条件');

DELETE FROM userTable WHERE id IN (SELECT id FROM ageTable WHERE age=18);