1.连表更新

准备两张表,id一样,但是姓名不一样,  需求根据id让姓名保持一致

 

执行的sql

 

UPDATE teacher_copy1 AS b
INNER JOIN teacher c ON b.TId = c.TId

set b.tname=c.tname

执行结果

2.连接删除

 

DELETE  a 
FROM
	teacher_copy1 AS a
	INNER JOIN teacher b ON a.TId = b.TId