使用带有IN运算符的CSV字符串时出错

Question

当我运行以下代码时

declare @aaa nvarchar(10)
set @aaa='1,2,3'
Select * from Customer where CustomerId in (convert(nvarchar,@aaa,10))

我收到此错误

Msg 8114, Level 16, State 5, Line 3
Error converting data type nvarchar to bigint.

请帮助

Answer 1

您不能使用INcvs字符串.如果您有Sql Server 2008,则可以使用表值参数(SQL Server 2008中的新增功能).通过创建实际的表参数类型来设置它:

CREATE TYPE IntTableType AS TABLE (ID bigint PRIMARY KEY)

那么你的程序是:

Create Procedure up_TEST
    @Ids IntTableType READONLY
AS

SELECT * 
    from Customer where CustomerId in (SELECT ID FROM @Ids)

RETURN 0
GO

如果你不能使用表值参数,请参阅:Erland Sommarskog的"使用表值参数的SQL Server 2008中的数组和列表",那么有很多方法可以在SQL Server中拆分字符串.本文涵盖了几乎所有方法的PRO和CON:

"表格值参数不能削减它时,SQL Server 2005及更高版本中的数组和列表"作者:Erland Sommarskog

您需要创建拆分功能.这是分割函数的使用方式:

SELECT
    *
    FROM YourTable                               y
    INNER JOIN dbo.yourSplitFunction(@Parameter) s ON y.ID=s.Value

我更喜欢使用数字表方法在TSQL中拆分字符串,但是有很多方法可以在SQL Server中拆分字符串,请参阅前面的链接,它解释了每个链接的PRO和CON.

要使Numbers Table方法起作用,您需要执行一次性表设置,这将创建一个Numbers包含1到10,000行的表:

SELECT TOP 10000 IDENTITY(int,1,1) AS Number
    INTO Numbers
    FROM sys.objects s1
    CROSS JOIN sys.objects s2
ALTER TABLE Numbers ADD CONSTRAINT PK_Numbers PRIMARY KEY CLUSTERED (Number)

设置Numbers表后,创建此拆分功能:

CREATE FUNCTION [dbo].[FN_ListToTable]
(
     @SplitOn  char(1)      --REQUIRED, the character to split the @List string on
    ,@List     varchar(8000)--REQUIRED, the list to split apart
)
RETURNS TABLE
AS
RETURN 
(

    ----------------
    --SINGLE QUERY-- --this will not return empty rows
    ----------------
    SELECT
        ListValue
        FROM (SELECT
                  LTRIM(RTRIM(SUBSTRING(List2, number+1, CHARINDEX(@SplitOn, List2, number+1)-number - 1))) AS ListValue
                  FROM (
                           SELECT @SplitOn + @List + @SplitOn AS List2
                       ) AS dt
                      INNER JOIN Numbers n ON n.Number < LEN(dt.List2)
                  WHERE SUBSTRING(List2, number, 1) = @SplitOn
             ) dt2
        WHERE ListValue IS NOT NULL AND ListValue!=''

);
GO 

您现在可以轻松拆分CSV字符串并在查询中使用它:

declare @aaa nvarchar(10)
set @aaa='1,2,3'
Select * from Customer where CustomerId in (SELECT ListValue FROM dbo.FN_ListToTable(',',@aaa))