基于SQL

Question

我有一个查询，它将执行6个表的连接并根据条件获取各种列。我想添加一个额外的过滤条件，只给那些count(distinct dateCaptured)>30的成员。我可以使用Group by和having获取满足此条件的成员列表。但由于这一个条件，我不想按其他列名分组。在这种情况下，我是否需要使用PARTITION BY。

示例表a

+-----+------------+--------------+
| Id  | Identifier | DateCaptured |
+-----+------------+--------------+
| 1   |      05548 | 2017-09-01   |
| 2   |      05548 | 2017-09-01   |
| 3   |      05548 | 2017-09-01   |
| 4   |      05548 | 2017-09-02   |
| 5   |      05548 | 2017-09-03   |
| 6   |      05548 | 2017-09-04   |
| 7   |      37348 | 2017-08-15   |
| 8   |      37348 | 2017-08-15   |
| .   |            |              |
| .   |            |              |
| .   |            |              |
| 54  |      37348 | 2017-10-15   |
+-----+------------+--------------+

查询

SELECT  a.value,
        b.value, c.value,
        d.value
        FROM Table a
    INNER JOIN Table b on a.Id=b.id
    INNER JOIN Table c on a.Id=c.Id and s.Invalid=0
    INNER JOIN Table d on a.Id=d.Id 

假设表a有超过30个标识符37348的记录。如何才能为上述查询获取此标识符。

这些是我对上述SELECT感兴趣的患者。

SELECT  a.Identifier,count(DISTINCT DateCaptured)
    FROM Table a
    INNER JOIN Table b on a.Id=b.id
    INNER JOIN Table c on a.Id=c.Id and s.Invalid=0
    INNER JOIN Table d on a.Id=d.Id 
    GROUP BY Identifier
    HAVING count(DISTINCT DateCaptured)>30

Answer 1

WITH cte as (
    SELECT  a.Identifier
    FROM Table a
    INNER JOIN Table b on a.Id=b.id
    INNER JOIN Table c on a.Id=c.Id and s.Invalid=0
    INNER JOIN Table d on a.Id=d.Id 
    GROUP BY Identifier
    HAVING count(DISTINCT DateCaptured) > 30
)
SELECT  a.value,
        b.value, c.value,
        d.value
FROM Table a
INNER JOIN Table b on a.Id=b.id
INNER JOIN Table c on a.Id=c.Id and s.Invalid=0
INNER JOIN Table d on a.Id=d.Id 
INNER JOIN cte on cte.Identifier = a.Identifier

Answer 2

SELECT  a.value,
        b.value, c.value,
        d.value
        FROM Table a
    INNER JOIN Table b on a.Id=b.id
    INNER JOIN Table c on a.Id=c.Id and s.Invalid=0
    INNER JOIN Table d on a.Id=d.Id 
WHERE a.Identifier IN (SELECT  a1.Identifier  
    FROM Table a1
    GROUP BY a1.Identifier HAVING count(DISTINCT a1.DateCaptured)>30)

Answer 3

如果多行真的在tableA，那么你可以这样做：

SELECT a.value, b.value, c.value, d.value
FROM (SELECT a.*, COUNT(*) OVER (PARTITION BY id) as cnt
      FROM a
     ) a INNER JOIN
     b 
     ON a.Id = b.id INNER JOIN 
     c 
     ON a.Id = c.Id AND s.Invalid = 0 INNER JOIN 
     d 
     ON a.Id = d.Id
WHERE a.cnt > 30;

注意：如果您仍然需要count(distinct)，则可以执行以下操作：

SELECT a.value, b.value, c.value, d.value
FROM (SELECT a.*, SUM(CASE WHEN seqnum = 1 THEN 1 ELSE 0 END) OVER (PARTITION BY id) as cnt
      FROM (SELECT a.*, ROW_NUMBER() OVER (PARTITION BY id ORDER BY DateCaptured) as seqnum
            FROM a
           ) a
     ) a INNER JOIN
     b 
     ON a.Id = b.id INNER JOIN 
     c 
     ON a.Id = c.Id AND s.Invalid = 0 INNER JOIN 
     d 
     ON a.Id = d.Id
WHERE a.cnt > 30;