ขอถามหน่อยครับ ทำไมผมเชือมต่อ database ได้แล้ว แต่ทำไมผมดึง table ไม่ได้อ่าครับ

Imports System.Data.SqlClient
Imports System.IO


Public Class Form1
    
    Dim Conn As SqlConnection
   
    Dim Invalid As Integer
    Dim rsToAffect As Long
   

    Dim connetionString As String = "Data Source=PONGWICS2014-PC; Initial Catalog=data1;User ID=sa;Password=Pong"
    Public sqlCommand As SqlCommand = New SqlCommand




    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

     
        Dim cnn As SqlConnection
        cnn = New SqlConnection(connetionString)
        Dim strCon As String = cnn.ToString
        Try
            cnn.Open()
            MsgBox("เชื่อมต่อได้แกล้ว  ")
            cnn.Close()
        Catch ex As Exception
            MsgBox("โอ้ๆ มันเกิดอะไรขึ้น ")
        End Try
    End Sub



    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim aaa As String = ""
        Dim bbb As String = ""
       
        Try

            Dim strSql As String = "select [user],[password] From inputdata where [user] = '" & user.Text & "' and [password] = '" & password.Text & "'"
            Dim da As New SqlDataAdapter(strSql, connetionString)
            Dim ds As New DataSet
            Dim dt As New DataTable

            da.Fill(ds)
            If ds.Tables(0).Rows.Count > 0 Then
                Form2.Show()
                Me.Hide()
            Else
                MessageBox.Show("ไม่พบผู้ใช้งาน หรือ รหัสผ่านไม่ถูกต้อง")
            End If
        Catch ex As Exception

            MessageBox.Show("error  TTT")

        End Try
    End Sub


End Class