2

我有 ac# 程序，想给存储过程一个参数。我的 c# 程序中的字符串就像“'Food','Clothes','Blood'”。

ALTER PROCEDURE [dbo].[GetLocations]
    @longMax float =100,
    @longMin float=0,
    @latMax float=100,
    @latMin float=0,
    @categoryFilter char(200) = ''
AS
BEGIN
    SET NOCOUNT ON;

    SELECT *
    FROM dbo.Locations
    WHERE longitude BETWEEN @longMin AND @longMax
      AND latitude BETWEEN @latMin AND @latMax
      AND subCategory in (@categoryFilter) 
END

结果应该给我 3 个条目，但结果是空的。我试图用另外两个 ' 来转义参数，但结果没有任何改变。

它适用于另一列上的 int 值，但不适用于字符。

如果有人可以提供帮助，那就太好了:)

4

6 回答 6

3

你得到一个空白的结果集，因为in clause它适用于一组数据。你正在传递一个 200 个单词的字符串。您的查询实际上是比较 subCategory 和 categoryFilter

您可以通过提供如下设置在管理工作室中明确尝试

SELECT *
FROM dbo.Locations
WHERE longitude BETWEEN @longMin AND @longMax
AND latitude BETWEEN @latMin AND @latMax
AND subCategory in ('abc','bcd','cde');

abc- 你的第一个类别过滤器，类似地 bcd 你的第二个等等。如果您在@categoryfilter 中有一组由逗号（，）分隔的数据，则首先拆分该字符串，然后使用IN Clause

于 2013-07-29T11:59:24.230 回答
2

我认为您需要拆分字符串参数-

DECLARE @categoryFilter VARCHAR(200) = 'Food,Clothes,Blood'

SELECT t.c.value('.', 'VARCHAR(50)')
FROM (
     SELECT ID = CAST ('<M>' + REPLACE(@categoryFilter, ',', '</M><M>') + '</M>' AS XML)
) r 
CROSS APPLY ID.nodes ('/M') t(c)

您的查询 -

ALTER PROCEDURE [dbo].[GetLocations] 

@longMax FLOAT = 100,
@longMin FLOAT = 0,
@latMax FLOAT = 100,
@latMin FLOAT = 0,
@categoryFilter VARCHAR(200) = 'Food,Clothes,Blood'

AS
BEGIN
     SET NOCOUNT ON;

     SELECT *
     FROM dbo.Locations
     WHERE longitude BETWEEN @longMin AND @longMax
          AND latitude BETWEEN @latMin AND @latMax
          AND (
               @categoryFilter = '' 
               OR 
               subCategory IN (
                    SELECT t.c.value('.', 'VARCHAR(50)')
                    FROM (
                         SELECT ID = CAST ('<M>' + REPLACE(@categoryFilter, ',', '</M><M>') + '</M>' AS XML)
                    ) r 
                    CROSS APPLY ID.nodes ('/M') t(c))
          )

END
于 2013-07-29T11:56:13.740 回答
1

尝试这个

ALTER PROCEDURE [dbo].[GetLocations]
@longMax float =100,
@longMin float=0,
@latMax float=100,
@latMin float=0,
@categoryFilter char(200) = ''
AS
BEGIN
    SET NOCOUNT ON;
   SET @categoryFilter =  REPLACE(@categoryFilter,',',''',''')

   DECLARE @QUERY VARCHAR(MAX)
   SET @QUERY = 'SELECT *
    FROM dbo.Locations
    WHERE longitude BETWEEN @longMin AND @longMax
      AND latitude BETWEEN @latMin AND @latMax
      AND subCategory in ('''+RTRIM(@categoryFilter)+''')'

    --PRINT (@QUERY) 

    EXEC (@QUERY) 


END
于 2013-07-29T12:04:37.710 回答
0

你可以尝试如下

ALTER PROCEDURE [dbo].[GetLocations]
    @longMax float =100,
    @longMin float=0,
    @latMax float=100,
    @latMin float=0,
    @categoryFilter char(200) = '',
    @Query varchar(2000)

AS
BEGIN
    SET NOCOUNT ON;

    Set @Query = 'SELECT *
            FROM dbo.Locations
           WHERE longitude BETWEEN @longMin AND @longMax
                  AND latitude BETWEEN @latMin AND @latMax
                  AND @categoryFilter IN (' + LTRIM(RTRIM(@categoryFilter)) + ')' 

    Exec(@Query)

END
于 2013-07-29T14:01:49.773 回答
0

尝试修剪传入的字符串-> RTRIM(@string)。

如果你使用 char，你总是需要修剪。

于 2013-07-29T12:02:05.667 回答
0

你可以使用喜欢：

ALTER PROCEDURE [dbo].[GetLocations]
    @longMax float =100,
    @longMin float=0,
    @latMax float=100,
    @latMin float=0,
    @categoryFilter char(200) = ''
AS
BEGIN
    SET NOCOUNT ON;

    SELECT *
    FROM dbo.Locations
    WHERE longitude BETWEEN @longMin AND @longMax
      AND latitude BETWEEN @latMin AND @latMax
      AND @categoryFilter LIKE '%' + subCategory + '%'
END
于 2013-07-29T11:58:54.447 回答