Simple VB Syntax to show some values from a database - mysql

Question

Im very new to Visual Basic (using visual studio 2010). Im just doing some tests to connect to a mysql database.
I do not know how to call these values once I have made the sql query.
How do I go about this, i.e. to show the values on the labels on a form?
Code:
Imports MySql.Data.MySqlClient
Public Class Form1
Dim ServerString As String = "Server = localhost; User Id = root; database = CALIBRA"
Dim SQLConnection As MySqlConnection = New MySqlConnection
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
SQLConnection.ConnectionString = ServerString
Try
If SQLConnection.State = ConnectionState.Closed Then
SQLConnection.Open()
MsgBox("Successfully connected to MySQL database.")
Else
SQLConnection.Close()
MsgBox("Connection is closed.")
End If
Catch ex As Exception
MsgBox(ex.ToString)
End Try
End Sub
Public Sub calibra_query(ByRef SQLStatement As String)
Dim cmd As MySqlCommand = New MySqlCommand
With cmd
.CommandText = SQLStatement
.CommandType = CommandType.Text
.Connection = SQLConnection
.ExecuteNonQuery()
End With
SQLConnection.Close()
MsgBox("Records Successfully Retrieved")
SQLConnection.Dispose()
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim SQLStatement As String = "SELECT Auto1, Auto2, TotalWeight FROM txticket WHERE TicketCode = '12210'"
calibra_query(SQLStatement)
Dim Automobile1, Automobile2, TotalWgt As Long
SOMETHING MISSING HERE
SOMETHING MISSING HERE
Label2.Text = Automobile1.ToString()
Label2.Text = Automobile2.ToString()
Label2.Text = TotalWgt.ToString()
End Sub
End Class
What do I put in the "SOMETHING MISSING HERE"? Much appreciation.

Answer 1

You will need a data reader in order to read the content of what is returned from the sql query. Your Sub calibra_query, is executing a nonreader, that isn't going to do what you need. You only want to use executeNonReader for things that you don't need a result from. (Like an Update statement for example)
You want something a bit more like this:
Dim cmd As MySqlCommand = New MySqlCommand
With cmd
.CommandText = SQLStatement
.CommandType = CommandType.Text
.Connection = SQLConnection
End With
Dim myReader as MySqlDataReader = myCommand.ExecuteReader
If myReader.Read Then
TextBox1.Text = myReader.GetString(0)
TextBox2.Text = myReader.Getstring(1)
TextBox3.Text = myReader.GetInt32(2)
End If
myReader.Close()
SQLConnection.Close()
MsgBox("Records Successfully Retrieved")
SQLConnection.Dispose()
I am assuming the types of the 3 fields in your query, and just outputting it to text boxes to give you the idea. That also assumes that you are only going to get one record as a result.
(Edit: to fix formatting)