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我有一组实体值表，并希望对结果进行透视。这是我正在寻找的效果，除了您看到使用 Common Table Expressions 的 SELECT stmt 还不能完全正确地工作。我的问题是：我是在正确的轨道上，还是有某种简单的枢轴命令？

USE TempDB
Declare @Person TABLE(
PersonID Int Identity(101,1))
INSERT INTO @Person DEFAULT VALUES
INSERT INTO @Person DEFAULT VALUES
INSERT INTO @Person DEFAULT VALUES
INSERT INTO @Person DEFAULT VALUES

DECLARE @Attribute TABLE(
AttributeID Int Identity(10,1) PRIMARY KEY,
AttributeName Varchar(MAX))
INSERT INTO @Attribute(AttributeName) VALUES('Firstname')
INSERT INTO @Attribute(AttributeName) VALUES('Lastname')

DECLARE @Pat TABLE( -- A Person's Attributes
PatID Int Identity,
PersonID Int,
AttributeID Int,
PatValue Varchar(MAX)
)
INSERT INTO @Pat(PersonID,AttributeID,PatValue) VALUES(101,10,'John')
INSERT INTO @Pat(PersonID,AttributeID,PatValue) VALUES(102,10,'Paul')
INSERT INTO @Pat(PersonID,AttributeID,PatValue) VALUES(103,10,'George')
INSERT INTO @Pat(PersonID,AttributeID,PatValue) VALUES(104,10,'Ringo')
INSERT INTO @Pat(PersonID,AttributeID,PatValue) VALUES(101,11,'Lennon')
INSERT INTO @Pat(PersonID,AttributeID,PatValue) VALUES(102,11,'McCartney')
INSERT INTO @Pat(PersonID,AttributeID,PatValue) VALUES(103,11,'Harrison')

SELECT Pat.PersonID,AttributeName,PatValue
FROM @Pat Pat
INNER JOIN @Person Person
ON Pat.PersonID = Person.PersonID
INNER JOIN @Attribute Attribute
ON Pat.AttributeID=Attribute.AttributeID
-- 

;WITH CTE1 AS(
    SELECT PersonID,PatValue AS FirstName
    FROM @Pat Pat
    INNER JOIN @Attribute Attribute
    ON Pat.AttributeID=Attribute.AttributeID
    WHERE AttributeName='FirstName'
)
,CTE2 AS(
    SELECT PersonID,PatValue AS LastName
    FROM @Pat Pat
    INNER JOIN @Attribute Attribute
    ON Pat.AttributeID=Attribute.AttributeID
    WHERE AttributeName='LastName'
)
SELECT Pat.PersonID,FirstName,LastName
FROM @Pat Pat
LEFT OUTER JOIN CTE1
ON Pat.PersonID=CTE1.PersonID
LEFT OUTER JOIN CTE2
ON Pat.PersonID=CTE2.PersonID
ORDER BY PersonID

我只想列出 4 个人的名单，包括他们的名字和姓氏。

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1 回答 1

3

好例子在这里

您的查询将如下所示：

SELECT PersonId, FirstName, LastName
FROM 
(
    -- your query
    SELECT Pat.PersonID,AttributeName,PatValue
    FROM @Pat Pat
    INNER JOIN @Person Person
    ON Pat.PersonID = Person.PersonID
    INNER JOIN @Attribute Attribute
    ON Pat.AttributeID=Attribute.AttributeID
) up
PIVOT (MAX(PatValue) FOR AttributeName IN (FirstName, LastName)) AS pvt
于 2009-09-10T21:27:52.440 回答