Question

我有一个具有唯一KEY（UserID和Type）

的表

UserID | Type | Column1 | Column2
----------------------------
 1     |   1  |  *NULL* |   1
 1     |   2  |   ABC   |  *NULL*
 1     |   3  |  *NULL* |   2
 2     |   1  |  *NULL* |   1
 2     |   2  |   CDE   |  *NULL*
 3     |   1  |  *NULL* |   3
 3     |   2  |   DTE   |  *NULL*

我正在尝试构建查询以搜索所有用户ID包含：

(Type=1 AND Column2=1) AND (Type=3 AND Column2=2)

Answer 1

这个问题与递归CTE无关。您可以使用聚合和having子句来解决它：

select userid
from t
where (Type = 1 AND Column2 = 1) OR (Type = 3 AND Column2 = 2)
group by userid
having count(distinct type) = 2;

Answer 2

With CTE(userid)  
AS
(
  SELECT userid
  FROM t
  WHERE (Type = 1 AND Column2 = 1)
)
SELECT userid 
FROM CTE  
WHERE EXISTS(
              SELECT 1 
              FROM CTE
              WHERE Type = 3 AND Column2 = 2 )

在CTE SQL查询中选择递归

2 个答案: