这句sql语句怎么改成left join的select 表2.a as a,表2.a as b,表2.a as c from 表1 a,表2 b,表2 c,表3 dwhere a.条件(+)=b.条件and a.条件(+)=c.条件and d.条件(+)=c.条件可能写错了,应该是这样的,抱歉select
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这句sql语句怎么改成left join的select 表2.a as a,表2.a as b,表2.a as c from 表1 a,表2 b,表2 c,表3 dwhere a.条件(+)=b.条件and a.条件(+)=c.条件and d.条件(+)=c.条件可能写错了,应该是这样的,抱歉select
这句sql语句怎么改成left join的
select 表2.a as a,表2.a as b,表2.a as c from 表1 a,表2 b,表2 c,表3 d
where a.条件(+)=b.条件
and a.条件(+)=c.条件
and d.条件(+)=c.条件
可能写错了,应该是这样的,抱歉
select 表2.a as a,表2.a as b,表3.a as c,表4.b as d from 表1 a,表2 b,表2 c,表3 d,表4 e
where a.条件(+)=b.条件
and a.条件(+)=c.条件
and d.条件(+)=c.条件
and e.条件(+)=a.条件
这句sql语句怎么改成left join的select 表2.a as a,表2.a as b,表2.a as c from 表1 a,表2 b,表2 c,表3 dwhere a.条件(+)=b.条件and a.条件(+)=c.条件and d.条件(+)=c.条件可能写错了,应该是这样的,抱歉select
left join?全是left join?
select 表2.a as a,表2.a as b,表3.a as c,表4.b as d
from 表1 a
left join 表2 b on a.条件(+)=b.条件
left join 表2 c on a.条件(+)=c.条件
left join 表3 d on d.条件(+)=c.条件
left join 表4 e on e.条件(+)=a.条件