多表连接时,要注意语法,应该如下:
select * from a inner join b on a.id=b.id
inner join c on a.id=c.id
错误写法:
select * from a inner join b
inner join c
on a.id=b.id
and a.id=c.id
多表连接时,要注意语法,应该如下:
select * from a inner join b on a.id=b.id
inner join c on a.id=c.id
错误写法:
select * from a inner join b
inner join c
on a.id=b.id
and a.id=c.id