Question

我有一个包含以下列的项目表

ProjectID, ProjectDescription

和列表数据表，其中包含以下列

ProjectID ListType Date Memo

每个项目在ListType表中都有许多列表类型条目。

我想要做的是运行一个返回类似

的查询

ProjectID, ProjectDescription, ListType1, ListType1.date, Listtype1.Memo, ListType2, ListType2.date, ListType.Memo

Againg，每个项目都与一些列表类型数据相关联。我正在使用Microsoft SQL 2000.所以Pivot关键字不起作用

Answer 1

您需要做的是创建动态SQL并为每个ListType构建其他CASE语句。我不得不做类似的工作，他们想要有关事件的某些信息。事件将以逗号分隔列表的形式传递，然后构建案例语句。

我有一个存储过程，用逗号分隔列表

创建一个表

CREATE PROCEDURE [dbo].[ListToTable]
    @vcList     VARCHAR(8000),
    @vcDelimiter    VARCHAR(8000),
    @TableName      SYSNAME,
    @ColumnName SYSNAME
AS
    SET NOCOUNT ON

    DECLARE @iPosStart  INT,
        @iPosEnd    INT,
        @iLenDelim  INT,
        @iExit      INT,
        @vcStr      varchar(8000),
        @vcSql      varchar(8000)

    SET @iPosStart = 1
    SET @iPosEnd = 1
    SET @iLenDelim = LEN(@vcDelimiter)

    SET @vcSql = 'INSERT ' + @TableName + ' (' + @ColumnName + ') VALUES ('''

    SET @iExit = 0

    WHILE @iExit = 0
    BEGIN
        SET @iPosEnd = CHARINDEX(@vcDelimiter, @vcList, @iPosStart)

        IF @iPosEnd <= 0
        BEGIN
            SET @iPosEnd = LEN(@vcList) + 1
            SET @iExit = 1
        END

        SET @vcStr = SUBSTRING(@vcList, @iPosStart, @iPosEnd - @iPosStart)

        EXEC(@vcSql + @vcStr + ''')')

        SET @iPosStart = @iPosEnd + @iLenDelim
    END

    RETURN 0

然后是动态SQL

DECLARE @Events VARCHAR(8000) = 'Event1,Event2,... Eventn'

CREATE TABLE #Events
    (
     EventName VARCHAR(MAX)
    )

EXEC [ListToTable] 
    @Events
   ,','
   ,'#Events'
   ,'EventName'

DECLARE @strCASE VARCHAR(MAX)
SET @strCase = ''

DECLARE Events_Cursor CURSOR 
FOR
SELECT EventName FROM [#Events] 

OPEN Events_Cursor
DECLARE @EventName VARCHAR(MAX)

FETCH NEXT FROM Events_Cursor INTO @EventName
WHILE ( @@FETCH_STATUS <> -1 ) 
    BEGIN
        IF ( @@FETCH_STATUS <> -2 ) 
            SET @strCase = @strCase + ',CASE WHEN [EventOpportunityProduct].[Name] = ''' + @EventName + ''' THEN EventOppertunityLineItem.[Trial_Status__c] ELSE NULL END [' + @EventName + ']'
        FETCH NEXT FROM Events_Cursor INTO @EventName
    END
CLOSE Events_Cursor
DEALLOCATE Events_Cursor

然后将@strCASE添加到SELECT语句中，例如

DECLARE @strSQL VARCHAR(MAX)
SET @strSQL = 'SELECT
    Field1
    ,Field2
    ' + @strCASE + '
   FROM Table'

EXEC (@strSQL)

交叉表查询

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