我有两个表
1)文档:代表文档
+----+----------+------+
| ID | Body | Type |
+----+----------+------+
| 1 | Ramesh | 1 |
| 2 | Khilan | 1 |
| 3 | kaushik | 4 |
| 4 | Chaitali | 2 |
| 5 | Hardik | 2 |
+----+----------+------+
2)目的地:代表文档的一方
+--------+------------+--------+
| UserId | DocumentId | Status |
+--------+------------+--------+
| 6 | 3 | 4 |
| 4 | 5 | 5 |
| 89 | 2 | 0 |
| 15 | 4 | 3 |
| 89 | 1 | 0 |
+--------+------------+--------+
状态列代表用户的文件夹,我想为每种文件夹的每种类型的计数,即使该文件夹为specifi用户为空,但是,如果需要他们,
+--------+--------+--------------+--------------+--------------+
| UserId | Status | Type 1 Count | Type 2 Count | Type 4 Count |
+--------+--------+--------------+--------------+--------------+
| 89 | 0 | 2 | 0 | 0 |
| 89 | 3 | 0 | 0 | 0 |
| 89 | 4 | 0 | 0 | 0 |
| 89 | 5 | 0 | 0 | 0 |
+--------+--------+--------------+--------------+--------------+
我面临的问题是,我找不到一种方法来获得用户没有加入的类型,我可以使用案例,但不能以我想要的形式
我的查询是:
`SELECT dd.[Status],
SUM(CASE WHEN d.[Type] = 1 THEN 1 ELSE 0 END) AS 'Type1Count'
SUM(CASE WHEN d.[Type] = 2 THEN 1 ELSE 0 END) AS 'Type2Count'
SUM(CASE WHEN d.[Type] = 4 THEN 1 ELSE 0 END) AS 'Type4Count'
FROM [User] u LEFT JOIN [Destination] dd ON u.[Id] = dd.[UserId]
LEFT JOIN [Document] d ON dd.[DocumentId] = d.[Id]
WHERE u.[Id] = @UserId`
结果是
+--------+--------+--------------+--------------+--------------+
| UserId | Status | Type 1 Count | Type 2 Count | Type 4 Count |
+--------+--------+--------------+--------------+--------------+
| 89 | 0 | 2 | 0 | 0 |
+--------+--------+--------------+--------------+--------------+
,因此将所有用户加入所有状态表(我在问题中的描述中都命名了此文件夹),然后再加入Document
和Destination
:
SELECT u.UserId, st.Status,
SUM(CASE WHEN doc.Type = 1 THEN 1 ELSE 0 END) AS [Type 1 Count],
SUM(CASE WHEN doc.Type = 2 THEN 1 ELSE 0 END) AS [Type 2 Count],
SUM(CASE WHEN doc.Type = 4 THEN 1 ELSE 0 END) AS [Type 4 Count]
FROM User u
CROSS JOIN Folder st
LEFT OUTER JOIN Destination d
ON d.UserId = u.UserId
AND d.Status = st.Status
LEFT OUTER JOIN Document doc
ON doc.ID = d.DocumentId
GROUP BY u.UserId, st.Status
ORDER BY u.UserId