sql where和and的区别

sql where和and的区别

select * from ClassInfo as a inner join StuInfo as b on a.ClassID=b.ClassID where Sex='男';
select * from ClassInfo as a inner join StuInfo as b on a.ClassID=b.ClassID and Sex='男';

第一个是 a与b在classid上等值连接，然后再按sex='男'过滤

第二个是a与b在classid且sex='男'做连接

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