Mysql中on,in,as,where的区别

答:Where查询条件,on内外连接时候用,as作为别名,in查询某值是否在某条件里 创建2个表:student,score student:  score: where SELECT * FROM student WHERE s_sex='男' 例如:on SELECT * FROM student LEFT JOIN score on student.s_id=score.s_id; on和w
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