将查询结果与另一个表联接

Question

我有以下查询

Select TA.Column1 , COALESCE(TE.Column2,TA.Column2) as  Mydata

from TableA TA
INNER JOIN TableB TB ON (TA.Column2 =TB.Column1)
LEFT JOIN TableC TC ON (TB.Column2  = TC.Column1)
LEFT JOIN TableD TD ON (TC.Column1 = TD.Column1)
LEFT JOIN TableE TE ON(TD.Column2 = TE.Column1)

为了让我期待的结果，因为我需要Join的MyData与另一列TableX

例如INNER JOIN TableX TX ON (TableX.Column1 = MyData)并在我的选择查询中包含TableX.COlumn2 。

我的查询是如何使用表TableX将COALESCE(TE.Column2,TA.Column2) as Mydata获取的值TableX

Answer 1

从表面上看，您应该能够执行此操作。 （您已经尝试过吗？）

Select TA.Column1 , COALESCE(TE.Column2,TA.Column2) as  Mydata, TX.Column2
from TableA TA
INNER JOIN TableB TB ON (TA.Column2 =TB.Column1)
LEFT JOIN TableC TC ON (TB.Column2  = TC.Column1)
LEFT JOIN TableD TD ON (TC.Column1 = TD.Column1)
LEFT JOIN TableE TE ON(TD.Column2 = TE.Column1)
LEFT JOIN TableX TX ON (COALESCE(TE.Column2,TA.Column2)) = TX.Column1