Public Shared sqlDataConnection As New SqlConnection( _
  My.Settings.DB_RezepturenConnection)
Public Shared sqlCommandString As String
Public Shared sqlCommand As New SqlCommand(sqlCommandString, sqlDataConnection)
Public Shared SFsqlDataadapter As New SqlDataAdapter(sqlCommand)
 
Shared Sub UpdateSQLCommand(ByVal CommandString As String)
  sqlCommand = New SqlCommand(CommandString , sqlDataConnection)
  SFsqlDataadapter = New SqlDataAdapter(sqlCommand)
End Sub

Private Sub ...
  UpdateSQLCommand("SELECT * FROM xyz ORDER BY Name")
  sqlDataConnection.Open()
  SFsqlDataadapter.Fill(dtXYZ)
 
  ...
 
End Sub