Attribute VB_Name = "db"
Public Function ExecuteSQL(ByVal SQL As String, MsgString As String) As ADODB.Recordset 'executes SQL and returns Recordset
   Dim cnn As ADODB.Connection  'create adodb connection when exec sql ,unefficient
   Dim rst As ADODB.Recordset
   Dim sTokens() As String ' what is meaning? define a string object as handling
   
   On Error GoTo ExecuteSQL_Error
   
   sTokens = Split(SQL)
   Set cnn = New ADODB.Connection
   cnn.Open ConnectString
   If InStr("INSERT,DELETE,UPDATE", UCase$(sTokens(0))) Then
      cnn.Execute SQL
      MsgString = sTokens(0) & " query successful"
   Else
      Set rst = New ADODB.Recordset
      rst.Open Trim$(SQL), cnn, adOpenDynamic, adLockOptimistic
      'rst.MoveLast
      'get RecordCount
      Set ExecuteSQL = rst
      MsgString = "查詢(xún)到" & rst.RecordCount & " 條記錄 "
   End If
ExecuteSQL_Exit:
   Set rst = Nothing
   Set cnn = Nothing
   Exit Function
   
ExecuteSQL_Error:
   MsgString = "查詢(xún)錯(cuò)誤: " & Err.Description
   Resume ExecuteSQL_Exit
End Function

Public Function ConnectString() As String
'returns a DB ConnectString
   db_path = "F:\vb code\vb_database\student\student.mdb;"
   ConnectString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & db_path & "Persist Security Info=False"
End Function