SQL查询-我在一个表中有三列，我需要将每一列的数据检查到另一个表中

Question

例如：

1   23  12              
33  AB1 A1              
5   AC4 B5              
77  AD9 B5              
7   93C 1       

。

A   B   C   D   E   F   G
        1       EA12    B5
        2       B29     7
        3       AD9     AC4
        7       AB1     1

结果

A         B                  C      
1   1     23    null    12  null    
33  null  AB1   AB1     A1  null    
5   5     AC4   AC4     B5  B5  
77  null  AD9   AD9     B5  B5  
7   7     93C   null    1   1   

Answer 1

我认为这是您所需要的：

with
x as (
  select c as v from t2
  union select e from t2
  union select g from t2
)
select
  a,
  (case when a in (select v from x) then a end) as found_a,
  b,
  (case when b in (select v from x) then b end) as found_b,
  c,
  (case when c in (select v from x) then c end) as found_c
from t1