mysql语句多表查询
mysql中select嵌套select_MYSQL查询之多表查询select嵌套
的三种形式。
iframe postmessage用法⼀、(having,group by,select嵌套放在select⾥)
⼆、(not in,distinct去重,select嵌套放在where⾥)rangefinder翻译
plc模拟器软件表的内容如下:
在msgbox函数中prompt
实现功能:查询没学过"张三"⽼师授课的同学的信息
实现语句:
SELECT student.s_id,student.s_name FROM student WHERE s_id
not in (SELECT distinct( score.s_id) FROM score,course,teacher WHERE score.c_id=course.
c_id AND course.t_id=teacher.t_id AND teacher.t_name='张三');
三,(select嵌套放在from⾥)表可参照2
实现功能:查询学过编号为"01"并且也学过编号为"02"的课程的同学的信息
实现语句:
memcached是数据库吗SELECT *from (SELECT s_id,s_score from score WHERE score.c_id ="01")as t1,(SELECT s_id,s_score from score WHERE score.c_id="02") as t2 WHERE t1.s_id=t2.s_id

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