Question

我有以下查询使用动态数据透视表以我期望的格式返回一些数据：

CREATE TABLE TEMPDOCS (DOCID INT, NAME VARCHAR(30))
CREATE TABLE PROVIDERIDS (ID INT, PARENTID INT, QUALIFIER VARCHAR(20), IDENTIFIER VARCHAR(30))
INSERT INTO TEMPDOCS VALUES (1, 'ROGER, HARPER')
INSERT INTO TEMPDOCS VALUES (2, 'WALTZ, HEALY')

INSERT INTO PROVIDERIDS VALUES (1, 1, 'DEA', 'D12345')
INSERT INTO PROVIDERIDS VALUES (2, 1, 'NPI', 'N12345')
INSERT INTO PROVIDERIDS VALUES (3, 1, 'LIC', 'L12345')
INSERT INTO PROVIDERIDS VALUES (4, 2, 'NPI', 'N23456')
INSERT INTO PROVIDERIDS VALUES (5, 2, 'REG', 'R23456')

DECLARE @cols AS NVARCHAR(MAX),
        @query  AS NVARCHAR(MAX),
        @id as int = 1;

SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(QUALIFIER) 
            FROM PROVIDERIDS
            LEFT OUTER JOIN TEMPDOCS on TEMPDOCS.DOCID = PROVIDERIDS.PARENTID
            WHERE DOCID = @id
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

set @query = 'SELECT DOCID, NAME, ' + @cols + ' from 
            (
                select TEMPDOCS.DOCID, TEMPDOCS.NAME, PROVIDERIDS.QUALIFIER, PROVIDERIDS.IDENTIFIER FROM TEMPDOCS
                LEFT OUTER JOIN PROVIDERIDS ON PROVIDERIDS.PARENTID=TEMPDOCS.DOCID
                WHERE TEMPDOCS.DOCID = ' + CAST(@ID AS VARCHAR(30)) + '
           ) x
            pivot 
            (
                MAX(IDENTIFIER)
                FOR QUALIFIER IN (' + @cols + ')
            ) p '


execute(@query)

我想将此代码转换为返回TABLE的用户定义函数。我尝试过但却无法使其发挥作用：

CREATE FUNCTION udfGetProviderIds (@DoctorId INT)
RETURNS TABLE
AS
BEGIN
    DECLARE @cols AS NVARCHAR(MAX),
        @query  AS NVARCHAR(MAX),
        @id as int = 1;

SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(QUALIFIER) 
            FROM PROVIDERIDS
            LEFT OUTER JOIN TEMPDOCS on TEMPDOCS.DOCID = PROVIDERIDS.PARENTID
            WHERE DOCID = @id
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

set @query = 'SELECT DOCID, NAME, ' + @cols + ' from 
            (
                select TEMPDOCS.DOCID, TEMPDOCS.NAME, PROVIDERIDS.QUALIFIER, PROVIDERIDS.IDENTIFIER FROM TEMPDOCS
                LEFT OUTER JOIN PROVIDERIDS ON PROVIDERIDS.PARENTID=TEMPDOCS.DOCID
                WHERE TEMPDOCS.DOCID = ' + CAST(@ID AS VARCHAR(30)) + '
           ) x
            pivot 
            (
                MAX(IDENTIFIER)
                FOR QUALIFIER IN (' + @cols + ')
            ) p '


    RETURN execute(@query)  
END

我收到以下错误：

Msg 102, Level 15, State 31, Procedure udfGetProviderIds, Line 32
Incorrect syntax near 'BEGIN'.

有没有办法在不声明RET子句中的TABLE和结构的情况下完成这项工作？或者，有没有更好的方法用动态Pivot创建UDF？

Answer 1

就像Aaron解释过你不能在UDF中使用动态sql但是我可以想办法将所有函数定义放在存储过程中，然后你可以将存储过程返回的结果输入到这样的临时表中

CREATE PROC usp_GetProviderIds 
@DoctorId INT
AS
BEGIN
    DECLARE @cols AS NVARCHAR(MAX),
        @query  AS NVARCHAR(MAX),
        @id as int = 1;

SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(QUALIFIER) 
            FROM PROVIDERIDS
            LEFT OUTER JOIN TEMPDOCS on TEMPDOCS.DOCID = PROVIDERIDS.PARENTID
            WHERE DOCID = @id
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

set @query = 'SELECT DOCID, NAME, ' + @cols + ' from 
            (
                select TEMPDOCS.DOCID, TEMPDOCS.NAME, PROVIDERIDS.QUALIFIER, PROVIDERIDS.IDENTIFIER FROM TEMPDOCS
                LEFT OUTER JOIN PROVIDERIDS ON PROVIDERIDS.PARENTID=TEMPDOCS.DOCID
                WHERE TEMPDOCS.DOCID = ' + CAST(@ID AS VARCHAR(30)) + '
           ) x
            pivot 
            (
                MAX(IDENTIFIER)
                FOR QUALIFIER IN (' + @cols + ')
            ) p '


    EXECUTE sp_Executesql @query  
END

然后，您可以通过执行以下操作将返回的结果集放入临时表中

CREATE TABLE #TempTable (Col1, Col2.....)
INSERT INTO #TempTable
EXEC usp_GetProviderIds @DoctorId

返回表的UDF中的SQL Server Dynamic Pivot

1 个答案: