将表变量与 sp_executesql 一起使用

Posted 2023-05-08

【中文标题】将表变量与 sp_executesql 一起使用

【英文标题】：using Table variable with sp_executesql

【发布时间】：2011-09-07 06:58:58

【问题描述】：

我有一个包含表变量的查询：

DECLARE @Selects    XML ;
SET @Selects='<Selects><Select><Q_ID>1</Q_ID><Q_DESC>nima1</Q_DESC></Select><Select><Q_ID>2</Q_ID><Q_DESC>nima2</Q_DESC></Select><Select><Q_ID>3</Q_ID><Q_DESC>nima3</Q_DESC></Select></Selects>'

DECLARE @QuestionID     NVARCHAR(10);
SET @QuestionID='a5';

DECLARE @TblSelect  TABLE 
(
    Q_ID            INT,
    Q_DESC          NVARCHAR(500)
)

INSERT INTO @TblSelect
(
    Q_ID,Q_DESC
)
SELECT  Q_Select.value('(Q_ID)[1]', 'int') AS 'Q_ID',
        Q_Select.value('(Q_DESC)[1]', 'nvarchar(500)') AS 'Q_DESC'
FROM    @Selects.nodes('/Selects/Select') AS AllSelects(Q_Select) 

DECLARE @Query      NVARCHAR(4000);
SET @Query=N'SELECT Q_ID,COUNT(Q_ID) FROM @TblSelect LEFT OUTER JOIN tblbase tb ON @TblSelect.Q_ID = @Col_Select group by Q_ID';

EXECUTE sp_executesql @Query,@TblSelect,@Col_Select

如何将表变量传递给我的查询？

【参考方案1】：

这是一个如何将表值参数传递给sp_executesql 的示例。变量必须通过readonly:

if exists (select * from sys.types where name = 'TestTableType')
    drop type TestTableType

create type TestTableType as table (id int)
go
declare @t TestTableType
insert @t select 6*7

exec sp_executesql N'select * from @var', N'@var TestTableType readonly', @t

这将打印Answer to the Ultimate Question of Life, the Universe, and Everything。

【讨论】：

你的意思是没有办法传递Table变量？这比我们的temprory table好吗？

@Nima：你可以传递一个表变量，事实上，这个例子就是这样做的。但表变量必须具有命名类型。所以它必须是declare @t TestTableType（命名类型）而不是declare @t (id int)（匿名类型）

【参考方案2】：

试试表格类型

DECLARE @Selects    XML ;
    SET @Selects='<Selects><Select><Q_ID>1</Q_ID><Q_DESC>nima1</Q_DESC></Select><Select><Q_ID>2</Q_ID><Q_DESC>nima2</Q_DESC></Select><Select><Q_ID>3</Q_ID><Q_DESC>nima3</Q_DESC></Select></Selects>'

    DECLARE @QuestionID     NVARCHAR(10);
    SET @QuestionID='a5';

    DECLARE TYPE TblSelect  AS TABLE 
    (
        Q_ID            INT,
        Q_DESC          NVARCHAR(500)
    )

    /* Declare a variable that references the type. */
    DECLARE @TblSelect 
    AS TblSelect ;

    INSERT INTO @TblSelect 
    (
        Q_ID,Q_DESC
    )

    SELECT  Q_Select.value('(Q_ID)[1]', 'int') AS 'Q_ID',
            Q_Select.value('(Q_DESC)[1]', 'nvarchar(500)') AS 'Q_DESC'
    FROM    @Selects.nodes('/Selects/Select') AS AllSelects(Q_Select) 

    DECLARE @Query      NVARCHAR(4000);
    SET @Query=N'SELECT Q_ID,COUNT(Q_ID) FROM @TblSelect LEFT OUTER JOIN tblbase tb ON @TblSelect.Q_ID = @Col_Select group by Q_ID';

    EXECUTE sp_executesql @Query,@TblSelect,@Col_Select

【讨论】：

我收到了这个错误：Msg 155, Level 15, State 2, Line 7 'TblSelect' is not a recognized CURSOR option，我不知道我的@Col_Select 有问题，我也收到了错误

查看此链接以获取更多参考msdn.microsoft.com/en-us/library/bb510489.aspx

DECLARE TYPE TblSelect AS TABLE 应该是CREATE TYPE TblSelect AS TABLE