存储过程中EXISTS子句的参数

Question

我有一张桌子DEPT,里面有两列 - ID, NAME.

将使用DEPT表中的ID显示搜索表单,用户可以选择任意数量的ID并提交表单,以获取相关信息NAMEs.

澄清/输入:

• 我不想构建动态查询 - 它不可管理.
• 我更喜欢使用表值参数的存储过程

还有其他解决办法吗？

注意:
此示例很简单,有1个表 - 在现实生活中,我必须处理超过6个表!

谢谢你的任何建议

Answer 1

CREATE TYPE dbo.DeptList
AS TABLE
(
  ID INT
);
GO

CREATE PROCEDURE dbo.RetrieveDepartments
  @dept_list AS dbo.DeptList READONLY
AS
BEGIN
  SET NOCOUNT ON;

  SELECT Name FROM dbo.table1 WHERE ID IN (SELECT ID FROM @dept)
  UNION ALL 
  SELECT Name FROM dbo.table2 WHERE ID IN (SELECT ID FROM @dept)
  -- ...
END
GO

现在在您的C#代码中,创建一个DataTable,用ID填充它,并将其传递给存储过程.假设您已经有一个名为tempList的列表,并且ID存储在id中:

DataTable tvp = new DataTable();
tvp.Columns.Add(new DataColumn("ID"));

foreach(var item in tempList)
{ 
    tvp.Rows.Add(item.id); 
}

using (connObject)
{
    SqlCommand cmd = new SqlCommand("StoredProcedure", connObject);
    cmd.CommandType = CommandType.StoredProcedure;
    SqlParameter tvparam = cmd.Parameters.AddWithValue("@dept_list", tvp);
    tvparam.SqlDbType = SqlDbType.Structured;
    ...
}

您还可以使用拆分功能.许多存在,如果你能保证输入是安全的(没有<,>,等等),这就是我喜欢的:

CREATE FUNCTION dbo.SplitInts_XML
(
   @List       VARCHAR(MAX),
   @Delimiter  CHAR(1)
)
RETURNS TABLE
AS
   RETURN 
   (  
      SELECT Item = y.i.value('(./text())[1]', 'int')
      FROM 
      ( 
        SELECT x = CONVERT(XML, '<i>' 
        + REPLACE(@List, @Delimiter, '</i><i>') + '</i>').query('.')
      ) AS a 
      CROSS APPLY x.nodes('i') AS y(i)
   );
GO

现在您的程序可以是:

CREATE PROCEDURE dbo.RetrieveDepartments
  @dept_list VARCHAR(MAX)
AS
BEGIN
  SET NOCOUNT ON;

  ;WITH d AS (SELECT ID = Item FROM dbo.SplitInts(@dept_list, ','))
  SELECT Name FROM dbo.table1 WHERE ID IN (SELECT ID FROM d)
  UNION ALL
  SELECT Name FROM dbo.table2 WHERE ID IN (SELECT ID FROM d)
  -- ...
END
GO