Sql server 蓝色nvarchar。如果我为参数选择了多个值，则会出现一般错误：数据集“DataSet1”的查询执行失败。Yes@J.Warren，原因如上所述。如果你把你的参数设为nvarchar，然后像我展示的那样做，它会工作的。我已经做了几十次了，我可以看到上面的

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蓝色

nvarchar

。如果我为参数选择了多个值，则会出现一般错误：

数据集“DataSet1”的查询执行失败。

Yes@J.Warren，原因如上所述。如果你把你的参数设为nvarchar，然后像我展示的那样做，它会工作的。我已经做了几十次了，我可以看到上面的查询可以将它声明为一个逗号分隔的字符串。但我不确定SSRS是否将多值参数作为单个逗号分隔字符串返回。如果是这样，为什么

选择@myParameter

在选择了一个选项的情况下有效，而在选择了多个值的情况下无效？好的，您可以这样做。。。创建一个过程，将参数值插入虚拟表中的nvarchar（max）列。然后你会看到它的真正价值。我不知道还有什么好建议。当我设置多值参数并将其传递给proc时，它总是一个逗号分隔的字符串。

SELECT *
FROM MyTable
WHERE MyColumn IN (@MyParameter)
  AND OtherCol > 0;

CREATE PROC dbo.YourProc @MultiParam varchar(8000), @TableName sysname AS
BEGIN

    DECLARE @SQL nvarchar(MAX);
    SET @SQL = N'SELECT * FROM dbo.' + QUOTENAME(@TableName) + N' MT CROSS APPLY dbo.DelimitedSplit8K_LEAD (@MultiParam,'','') DS WHERE MT.MyColumn = DS.item;';

    EXEC sp_executesql @SQL, N'@MultiParam varchar(8000)', @MultiParam;
END;
GO

@myParameter = 'FirstValue, Second Value Selected, Third Val'

select *
from my table
where my column in ('FirstValue, Second Value Selected, Third Val')

select *
from my table
where my column in ('FirstValue', 'Second Value Selected', 'Third Val') 

CREATE FUNCTION [dbo].[DelimitedSplit8K]
--===== Define I/O parameters
        (@pString VARCHAR(8000), @pDelimiter CHAR(1))
--WARNING!!! DO NOT USE MAX DATA-TYPES HERE!  IT WILL KILL PERFORMANCE!
RETURNS TABLE WITH SCHEMABINDING AS
 RETURN
--===== "Inline" CTE Driven "Tally Table" produces values from 1 up to 10,000...
     -- enough to cover VARCHAR(8000)
  WITH E1(N) AS (
                 SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
                 SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
                 SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
                ),                          --10E+1 or 10 rows
       E2(N) AS (SELECT 1 FROM E1 a, E1 b), --10E+2 or 100 rows
       E4(N) AS (SELECT 1 FROM E2 a, E2 b), --10E+4 or 10,000 rows max
 cteTally(N) AS (--==== This provides the "base" CTE and limits the number of rows right up front
                     -- for both a performance gain and prevention of accidental "overruns"
                 SELECT TOP (ISNULL(DATALENGTH(@pString),0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
                ),
cteStart(N1) AS (--==== This returns N+1 (starting position of each "element" just once for each delimiter)
                 SELECT 1 UNION ALL
                 SELECT t.N+1 FROM cteTally t WHERE SUBSTRING(@pString,t.N,1) = @pDelimiter
                ),
cteLen(N1,L1) AS(--==== Return start and length (for use in substring)
                 SELECT s.N1,
                        ISNULL(NULLIF(CHARINDEX(@pDelimiter,@pString,s.N1),0)-s.N1,8000)
                   FROM cteStart s
                )
--===== Do the actual split. The ISNULL/NULLIF combo handles the length for the final element when no delimiter is found.
 SELECT ItemNumber = ROW_NUMBER() OVER(ORDER BY l.N1),
        Item       = SUBSTRING(@pString, l.N1, l.L1)
   FROM cteLen l
;

create table mytable (Names varchar(64))

insert into mytable values ('Bob'),('Mary'),('Tom'),('Frank')

--this is your parameter from SSRS    
declare @var varchar(4000) = 'Bob,Mary,Janice,Scarlett'

select distinct mytable.*
from mytable
cross apply dbo.DelimitedSplit8K(@var,',') spt
where spt.Item = mytable.Names

INSERT INTO DebugLog 
SELECT CAST(SQL_VARIANT_PROPERTY(@productIds,'BaseType') AS VARCHAR(MAX))

SELECT p.Id
INTO #tempProdIds
FROM Products p WHERE p.Id IN @productIds

SET @query +='
....
JOIN #tempProdIds tpi on tl.Product = tpi.Id
....
'
EXEC(@query)