sel="select A.usertype,B.username from A,B where A.ID=B.ID"A表中usertype字段有3种值分别为 新客户,老客户,免费客户
现在我想求出新客户,老客户,免费客户的数量分别是多少?应该怎么处理??
我使用SqlDataReader DR=exe.(sel);
While(DR.read())
{
DR["usertype"]
}
这种方法不对!!
应该怎么做???
现在我想求出新客户,老客户,免费客户的数量分别是多少?应该怎么处理??
我使用SqlDataReader DR=exe.(sel);
While(DR.read())
{
DR["usertype"]
}
这种方法不对!!
应该怎么做???
-------------------------------------------
sel="select A.usertype,B.username from A,B where A.ID=B.ID"这条语句还要生成
DataGrid的数据源!那种写法恐怕不行吧??
DataSet ds = SqlHelper.ExecuteDataset("连接字符串", CommandType.Text, sql);
return ds.Tables[0];注意:using Microsoft.ApplicationBlocks.Data;
必须要有这个包才可以
sel="select A.usertype, count(A.usertype) as 数量 from A group by A.usertype"
我想知道,用什么方法能得到每一类的值?
是用ExecuteScalar()吗????
sel="select A.usertype,B.username,(Select Count(*) From B Where A.ID = B.ID) As CountSum from A,B where A.ID=B.ID"我的不行???
用什么方法执行啊???
ExecuteScalar()?
SqlDataAdapter()???
不要只写sql语句!!谢谢!!!
try{
while(DR.Read())
{
if(DR["客户类别"].ToString().Trim()=="新客户")
{
a1++;
}
if(DR["客户类别"].ToString().Trim()=="老客户")
{
a2++;
}
if(DR["客户类别"].ToString().Trim()=="潜在")
{
a3++;
}
if(DR["客户类别"].ToString().Trim()=="免费")
{
a4++;
}
if(DR["客户类别"].ToString().Trim()=="掉线")
{
a5++;
}
a++;
}
}
catch(Exception ex)
{
this.Label13.Text=ex.ToString();
}
conn.open()
dim strCmd as string
strCmd = "Select ...."
dim cmd as new sqlcommand(strcmd,conn)
Dim dr As SqlDataReader
dr = cmd1.ExecuteReader()
while dr.read()
Select Case dr.Items(0)
Case "新客户"
a1 = a1+1
Case "老客户"
a2 = a2+1
....
End Select
Loopdr.close
cmd.close
conn.close
select A.usertype,B.username from A,B where A.ID=B.ID ) a group by a.usertype
替换你的 SQL 语句,Try.....