SQL查询 - 在另一个查询中使用信息

Question

这是我的查询。我删除了表格名称以及其他我选择的内容，以方便阅读。

Select 
    b.Key1, 
    b.Key2 
From 
    b 

    left join c 
    on c.MailingKey = b.MailingKey 

    left join d 
    on d.OrderLineKey = c.OrderLineKey 

    left join e 
    on e.ShipKey = d.ShipKey 

    left join g 
    on d.ShipKey5 = g.ShipKey5 

    left join a 
    on a.DocKey = b.OrderKey 

    left join f 
    on f.pMethKey = b.MethKey 

我需要使用键1和键2，我选择另一个查询，以获取有关从另一个表键（位置，身份证等）的更多信息。我想我需要在这个原始查询中创建2个循环，并将它们全部加入。所以这样的事情：

Select b.Key1, b.Key2, h.*, i.* 
From b left join 
c on c.MailingKey = b.MailingKey left join 
d on d.OrderLineKey = c.OrderLineKey left join 
e on e.ShipKey = d.ShipKey left join 
g on d.ShipKey5 = g.ShipKey5 left join 
a on a.DocKey = b.OrderKey left join 
f on f.pMethKey = b.MethKey left join 
( 
Select* 
From table l 
Where ID = b.Key1 
) h left join ( 
Select* 
From table l 
Where ID = b.Key2 
) i 

我只是不知道如何写等于b.Key1和b.Key2。

我正在使用Microsoft Sql Server Management。

Answer 1

公共表表达式：

with cte as (
Select b.Key1, b.Key2 
From b left join 
c on c.MailingKey = b.MailingKey left join 
d on d.OrderLineKey = c.OrderLineKey left join 
e on e.ShipKey = d.ShipKey left join 
g on d.ShipKey5 = g.ShipKey5 left join 
a on a.DocKey = b.OrderKey left join 
f on f.pMethKey = b.MethKey) 
Select * from CTE 
INNER JOIN othertable o 
on b.key1=o.key1 
and b.key2=o.key2 

或你的意思是......

内嵌视图：

Select * 
from otherTable 
INNER JOIN (
Select b.Key1, b.Key2 
From b left join 
c on c.MailingKey = b.MailingKey left join 
d on d.OrderLineKey = c.OrderLineKey left join 
e on e.ShipKey = d.ShipKey left join 
g on d.ShipKey5 = g.ShipKey5 left join 
a on a.DocKey = b.OrderKey left join 
f on f.pMethKey = b.MethKey) CTE 
on b.key1=o.key1 
and b.key2=o.key2 

还是你的意思....别的东西？

也许是：使用OR语句......

Select * 
from otherTable o 
INNER JOIN (
Select b.Key1, b.Key2 
From b left join 
c on c.MailingKey = b.MailingKey left join 
d on d.OrderLineKey = c.OrderLineKey left join 
e on e.ShipKey = d.ShipKey left join 
g on d.ShipKey5 = g.ShipKey5 left join 
a on a.DocKey = b.OrderKey left join 
f on f.pMethKey = b.MethKey) CTE 
on o.key1=cte.key1 
OR o.key2=cte.key2 

或者也许......一个在声明

Select * 
from otherTable o 
INNER JOIN (
Select b.Key1, b.Key2 
From b left join 
c on c.MailingKey = b.MailingKey left join 
d on d.OrderLineKey = c.OrderLineKey left join 
e on e.ShipKey = d.ShipKey left join 
g on d.ShipKey5 = g.ShipKey5 left join 
a on a.DocKey = b.OrderKey left join 
f on f.pMethKey = b.MethKey) CTE 
on o.key1 IN (cte.key1, cte.key2)