SQL Where in (1,2,3,4) 换成字段一列的值

                DECLARE @resource VARCHAR(300) ;
               SELECT   @ resource  = SUBSTRING(CourseIdList, 1, LEN(CourseIdList) - 1)
                SELECT  SUM(rlong * 60)
                FROM    r_resource
                WHERE   id IN ( @resource)
换成

                DECLARE @resource VARCHAR(300) ；
               SELECT   @ resource  = SUBSTRING(CourseIdList, 1, LEN(CourseIdList) - 1)
                SELECT  @SumStudyTime = SUM(rlong * 60)
                FROM    r_resource
                where charindex(','+cast(id  as varchar(10))+',',','+@resource+',')>0  

SELECT cid,id FROM  dbo.test
where charindex(','+CAST(Cid AS varchar(10))+',',',3,')>0
注释：cid  前后加上 逗号，在后面的字符创中获取下标