加入删除

Question

我正在使用mysql：

• btableA有tableB_id列
• tableB有some_interestring_column_on_TableB

我想要（下面的伪sql）：

delete from tableA 
 where the associated row in tableB (via tableB_id) has  
     some_interestring_column_on_TableB = 'interestingValue'

请帮我把伪sql翻译成真正的sql。

Answer 1

试试这个：

 DELETE TableA
 WHERE tableB_id IN (
    SELECT id FROM TableB 
    WHERE  interestring_column='pizza');

Answer 2

MySQL supports JOINs in the DELETE statement, as well as deleting from multiple tables in a single statement。以下内容仅从TABLEA中删除：

DELETE ta
  FROM TABLEA ta
  JOIN TABLEB tb ON b.id = a.tableb_id
                AND b.col = 'some value'

如果要从两个表中删除，请使用：

DELETE ta, tb
  FROM TABLEA ta
  JOIN TABLEB tb ON b.id = a.tableb_id
                AND b.col = 'some value'

也就是说，这种支持在其他数据库中非常罕见 - 在大多数情况下，您必须使用IN或EXISTS。

Answer 3

我不知道mysql语法，但我想的是（来自mssql）：

delete from tableA 
where tableA.tableB_id in 
   (select tableB.id from tableB 
   where tableB.some_interesting_column_on_TableB = 'interestingValue')