t-sql 将列转置为行
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【中文标题】t-sql 将列转置为行【英文标题】：t-sql transpose column into row 【发布时间】：2021-02-15 13:26:00 【问题描述】：我这里有 3 张桌子：
Property 表。
PropertyAudit - 捕获在“属性”表中所做的一项或多项更改。
PStatus - 这是 StautsID 列的查找表。
这是我目前所拥有的。
这是表格脚本和示例数据：
CREATE TABLE Property
(
PropertyID INTEGER NOT NULL PRIMARY KEY
,StatusID INTEGER NOT NULL
,Country VARCHAR(11) NOT NULL
,Town VARCHAR(10) NOT NULL
,LastChangedBy VARCHAR(20) NOT NULL
,LastChanged VARCHAR(23) NOT NULL
);
INSERT INTO Property (
PropertyID
,StatusID
,Country
,Town
,LastChangedBy
,LastChanged
)
VALUES (
73555
,1
,'NoMansLand'
,'BEEREN'
,'Agent009'
,'2020-10-15 12:41:14.280'
);
INSERT INTO Property (
PropertyID
,StatusID
,Country
,Town
,LastChangedBy
,LastChanged
)
VALUES (
72896
,6
,'Neverlands'
,'RIDDERK'
,'Agent007'
,'2020-08-10 08:41:22.447'
);
CREATE TABLE PropertyAudit
(
AID INTEGER NOT NULL PRIMARY KEY
,PropertyID INTEGER NOT NULL
,StatusID INTEGER NOT NULL
,LastChangedBy VARCHAR(20) NOT NULL
,LastChanged VARCHAR(23) NOT NULL
)
INSERT INTO PropertyAudit (
AID
,PropertyID
,StatusID
,LastChangedBy
,LastChanged
)
VALUES (
12340
,73555
,7
,'Agent009'
,'2020-10-15 12:41:14.280'
);
INSERT INTO PropertyAudit (
AID
,PropertyID
,StatusID
,LastChangedBy
,LastChanged
)
VALUES (
12341
,73555
,6
,'Agent007'
,'2020-08-24 08:10:53.223'
);
INSERT INTO PropertyAudit (
AID
,PropertyID
,StatusID
,LastChangedBy
,LastChanged
)
VALUES (
12342
,73555
,5
,'Agent009'
,'2020-02-13 14:38:10.913'
);
INSERT INTO PropertyAudit (
AID
,PropertyID
,StatusID
,LastChangedBy
,LastChanged
)
VALUES (
12343
,73555
,3
,'Agent009'
,'2020-02-13 14:33:25.967'
);
INSERT INTO PropertyAudit (
AID
,PropertyID
,StatusID
,LastChangedBy
,LastChanged
)
VALUES (
12344
,73555
,2
,'Agent009'
,'2020-02-10 13:37:57.527'
);
CREATE TABLE PStatus
(
ID INTEGER NOT NULL PRIMARY KEY
,StatusName VARCHAR(20) NOT NULL
,LastChangedBy VARCHAR(20) NOT NULL
,LastChanged VARCHAR(23) NOT NULL
);
INSERT INTO PStatus (
ID
,StatusName
,LastChangedBy
,LastChanged
)
VALUES (
1
,'REJECTED'
,'dbo'
,'2013-05-28 17:02:42.977'
);
INSERT INTO PStatus (
ID
,StatusName
,LastChangedBy
,LastChanged
)
VALUES (
2
,'NEW Contract'
,'dbo'
,'2013-05-28 17:02:42.977'
);
INSERT INTO PStatus (
ID
,StatusName
,LastChangedBy
,LastChanged
)
VALUES (
3
,'ACTIVE Contract'
,'dbo'
,'2013-10-15 12:41:14.280'
);
INSERT INTO PStatus (
ID
,StatusName
,LastChangedBy
,LastChanged
)
VALUES (
4
,'MONITOR'
,'dbo'
,'2013-10-15 12:41:14.280'
);
INSERT INTO PStatus (
ID
,StatusName
,LastChangedBy
,LastChanged
)
VALUES (
5
,'DEAL'
,'dbo'
,'2013-10-15 12:41:14.280'
);
INSERT INTO PStatus (
ID
,StatusName
,LastChangedBy
,LastChanged
)
VALUES (
6
,'DEALT'
,'dbo'
,'2013-10-15 12:41:14.280'
);
INSERT INTO PStatus (
ID
,StatusName
,LastChangedBy
,LastChanged
)
VALUES (
7
,'COMPLETED'
,'dbo'
,'2013-10-15 12:41:14.280'
);
INSERT INTO PStatus (
ID
,StatusName
,LastChangedBy
,LastChanged
)
VALUES (
8
,'ABORTED'
,'dbo'
,'2013-10-15 12:41:14.280'
);
这就是我想要实现的目标。
最终输出：
+---------+---------------+----------------+-----------+-------------------------+
| PRD Ref | Latest_Status | Opening_Status | ChangedBy | ChangedOn |
+---------+---------------+----------------+-----------+-------------------------+
| 73555 | COMPLETED | NEW CONTRACT | Agent009 | 2020-10-15 12:41:14.280 |
+---------+---------------+----------------+-----------+-------------------------+
这是我尝试过的。
如何引入 2 列“Lastest_Status”和“Opening_Status”并从 Status 列复制值。
SELECT prop.[PropertyID] AS "PRD Ref"
,(
SELECT [StatusName]
FROM [PStatus]
WHERE pa.StatusID = [ID]
) AS "Status"
,pa.[LastChangedBy] AS "ChangedBy"
,pa.[LastChanged] AS "ChangedOn"
FROM [PropertyAudit] pa
INNER JOIN [Property] prop ON pa.PropertyID = prop.PropertyID
WHERE pa.PropertyID = 73555
ORDER BY pa.PropertyID DESC
+---------+-----------------+-----------+-------------------------+
| PRD Ref | Status | ChangedBy | ChangedOn |
+---------+-----------------+-----------+-------------------------+
| 73555 | COMPLETED | Agent009 | 2020-10-15 12:41:14.280 |
| 73555 | DEALT | Agent007 | 2020-08-24 08:10:53.223 |
| 73555 | DEAL | Agent009 | 2020-02-13 14:38:10.913 |
| 73555 | ACTIVE Contract | Agent009 | 2020-02-13 14:33:25.967 |
| 73555 | NEW Contract | Agent009 | 2020-02-10 13:37:57.527 |
+---------+-----------------+-----------+-------------------------+
非常感谢。
【问题讨论】：
【参考方案1】：这是使用窗口函数和条件聚合的一种方法：
select p.propertyid,
max(case when pa.rn_desc = 1 then s.statusname end) last_status,
max(case when pa.rn_asc = 1 then s.statusname end) opening_status,
p.lastchangedby,
p.lastchanged
from property p
inner join (
select pa.*,
row_number() over(partition by propertyid order by lastchanged) rn_asc,
row_number() over(partition by propertyid order by lastchanged desc) rn_desc
from propertyaudit pa
) pa on pa.propertyid = p.propertyid
inner join pstatus s on s.id = pa.statusid
where 1 in (rn_asc, rn_desc)
group by p.propertyid, p.lastchangedby, p.lastchanged
请注意，您实际上并不需要表 property 来获得您想要的结果。我们可以进一步挖掘审计表，如下所示：
select pa.propertyid,
max(case when pa.rn_desc = 1 then s.statusname end) last_status,
max(case when pa.rn_asc = 1 then s.statusname end) opening_status,
max(case when pa.rn_desc = 1 then pa.lastchangedby end) lastchangedby,
max(case when pa.rn_desc = 1 then pa.lastchanged end) lastchanged
from (
select pa.*,
row_number() over(partition by propertyid order by lastchanged) rn_asc,
row_number() over(partition by propertyid order by lastchanged desc) rn_desc
from propertyaudit pa
) pa
inner join pstatus s on s.id = pa.statusid
where 1 in (rn_asc, rn_desc)
group by pa.propertyid
Demo on DB Fiddle - 两个查询都产生：
物业编号 |最后状态 |开放状态 |最后更改者 |最后更改 ---------: | :------------ | :------------- | :------------ | :------------------------ 73555 |已完成 |新合同 |代理009 | 2020-10-15 12:41:14.280【讨论】：
太棒了，感谢您的快速回复。我使用了第一种方法，因为我将从属性中提取其他列。向你致敬.... 快速提问。我在哪里可以添加索引列以按顺序排列。如果这是有道理的。我试图在开头添加以下行，但它开始中断。,ROW_NUMBER() OVER(PARTITION BY PropertyID ORDER BY statusname DESC) AS "INDEX" 如果可能的话。以上是关于t-sql 将列转置为行的主要内容，如果未能解决你的问题，请参考以下文章