用datareader和sql添加一列 [英] Adding up a column with datareader and sql

问题描述

我想在一列中添加每一行。



我知道我在博士（i）上缺少一个整数改变的东西。



如果有更简单的方法请告诉我。

I would like to add up every row in a column.

I know I am missing a integer changing thing on dr(i).

If there are easier methods please let me know.

Sub Add()
        cmdStr = "SELECT [col3] FROM [table1];"
        End Select
        i = 0
        connStr = "server=myServer;initial catalog=myDB;uid=myID;pwd=myPassword"
        Using conn As New SqlConnection(connStr)
            conn.Open()
            Using cmd As New SqlCommand(cmdStr, conn)
                Using dr As SqlDataReader = cmd.ExecuteReader()
                    While dr.Read()
                        count = count + dr(i)
                        i = i + 1
                    End While
                End Using
            End Using
        End Using
        TextBox2.Text = count
End Sub

推荐答案

1）要从数据库中选择总和，请使用类似的东西。

1) To select sum from the database use something like..

cmdStr = "SELECT SUM(col3) FROM table1"

2）要从sqldatareader获取整数，请使用 dr.GetInt ...

来自dotnetperls的 sqldatareader示例 [ ^ ]

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