Question

I would like to fire an SQL Query from my ASP.NET page (vb), what the query will do is to look for the maximum value from a column and then return that value and place it into a label in the webpage.

Currently i dont know to fire the SQL command and then return with the value, a correction to my code is hihgly appreciated.

Dim Con As New SqlConnection
        Dim SQL As String
        Con.ConnectionString = "Data Source=WCRDUSMJEMPR9\SQLEXPRESS;Initial Catalog=MicroDB;Integrated Security=True"
        Con.Open()
        SQL = "SELECT MAX(ID_ControlCharts) FROM ControlCharts"
        Label123.Text = SQL

The code above is not working, i know that i need to execute the query however i’m totally lost.

Answer 1

You need to create sql command and call executescalar method.

Ex:

Dim Con As New SqlConnection
Dim SQL As String
Con.ConnectionString = "Data Source=WCRDUSMJEMPR9\SQLEXPRESS;Initial
    Catalog=MicroDB;Integrated Security=True"
Con.Open()
Dim cmd as new SQLCommand(sql,Con)
Dim obj = cmd.ExecuteScalar()
if(obj!=null)
 Label123.Text = obj.ToString()
end if

Con.Close()