SUM[ALL[DISTINCT] 表达式)
在sum语句中,as关键字是比较常用的,其主要就是为某个字符串为表达式指定别名。下面,我们在数据库中写个sum函数的存储过程:
USE [Study]
GO
Create Procedure count
AS
select SUM(Num) as NumTotal
from Counts
GO
然后,我们在asp.net的.cs中用C#,ado.net调用这个存储过程名来实现统计计数和。 int totalNum = 0;
string datastr = "server=.;database=Study;user id=sa;password=1234567890";
SqlConnection con = new SqlConnection(datastr);
con.Open();
SqlCommand mycmd = new SqlCommand("count", con);
mycmd.CommandType = CommandType.StoredProcedure;
SqlDataReader read =mycmd.ExecuteReader();
if (read.Read())
{
totalNum = Convert.ToInt32(read["NumTotal"].ToString());
}
read.Close();
mycmd.Dispose();
con.Close();
return totalNum;