SQL SERVER SELECT 外加列
SQL SERVER SELECT 叠加列
假如表1有 A、B列,表2有 C 列。
A B
1 1
1 0
C
true
false
SELECT 如何才能输出 :
A B C
1 1 true
1 0 false
----------------?分组查询?
------解决思路----------------------
------解决思路----------------------
SELECT a ,
b ,
d
FROM ( SELECT a ,
b ,
ROW_NUMBER() OVER ( ORDER BY a ) c
FROM ( SELECT 1 a ,
1 b
UNION ALL
SELECT 1 a ,
0 b
) t
) k
INNER JOIN ( SELECT d ,
ROW_NUMBER() OVER ( ORDER BY d DESC ) l
FROM ( SELECT 'ture' d
UNION ALL
SELECT 'false' d
) f
) g ON k.c = g.l
假如表1有 A、B列,表2有 C 列。
A B
1 1
1 0
C
true
false
SELECT 如何才能输出 :
A B C
1 1 true
1 0 false
----------------?分组查询?
------解决思路----------------------
select a,b,case when a=1 and b=1 then 'true' else 'false' end as c from [表1]
------解决思路----------------------
SELECT a ,
b ,
d
FROM ( SELECT a ,
b ,
ROW_NUMBER() OVER ( ORDER BY a ) c
FROM ( SELECT 1 a ,
1 b
UNION ALL
SELECT 1 a ,
0 b
) t
) k
INNER JOIN ( SELECT d ,
ROW_NUMBER() OVER ( ORDER BY d DESC ) l
FROM ( SELECT 'ture' d
UNION ALL
SELECT 'false' d
) f
) g ON k.c = g.l