Question

I am using Access 2003 to access data stored in a SQL Server database via ADO. Most often I obtain the data using stored procedures. I execute the stored procedures via ADO in a separate function that returns a recordset. When returning a recordset from a function where is the best place to close the recordset and release it’s hold on memory? Is it done in the function that returns the recordset or is it done in the sub/function that calls the function executing the ADO code? Here is an example …

Here is the calling method

Public Sub CallingMethod()
  Dim rs As ADODB.Recordset
  Set rs = GetDataFromDatabase()
  Set myListBox.Recordset = rs
  rs.Close
  Set rs = Nothing
End Sub

Here is the Method that actually executes the stored procedure and returns it to the calling method

Public Function GetDataFromDatabase()
  Dim cnn As ADODB.Connection
  Dim rs As ADODB.Recordset

  Set cnn = New ADODB.Connection
  cnn.ConnectionString = myConnectionString
  cnn.Open

  Set rs = New ADODB.Recordset
  Set rs.ActiveConnection = cnn
  rs.Source = "EXEC uspMyStoredProcedure"

  rs.LockType = adLockOptimistic
  rs.CursorType = adOpenStatic
  rs.CursorLocation = adUseClient
  rs.Open

  Set GetDataFromDatabase = rs

  Set rs = Nothing
  Set cnn = Nothing

End Function

What I am wondering is where I should be closing the recordset and setting it equal to nothing. Am I doing it in both places without needing to? Just looking for best practices. Thank you.

Answer 1

I’m not sure what’s proper, either. I tried an approach where the calling code creates the connection object and passes it to the function. The caller is responsible for disposing of both the connection and recordset objects. It’s quick & dirty because I didn’t want to invest more in it only to find out my approach is just plain boneheaded.

Public Sub test_GetDataFromSP()
    Dim cnn As ADODB.Connection
    Dim rs As ADODB.Recordset

    Set cnn = New ADODB.Connection
    cnn.ConnectionString = "DRIVER=SQL Server;SERVER=VM2003\SQLEXPRESS;" & _
        "Trusted_Connection=Yes;DATABASE=Inventory"
    cnn.Open
    Set rs = GetDataFromSP("GetCenterCodes", cnn, "14, 14, 501")
    rs.MoveLast
    Debug.Print rs.RecordCount
    rs.Close
    Set rs = Nothing
    cnn.Close
    Set cnn = Nothing
End Sub

Public Function GetDataFromSP(ByVal pProc As String, _
    ByRef pConnection As ADODB.Connection, _
    Optional ByVal pArguments As String) As ADODB.Recordset

    Dim rs As ADODB.Recordset
    Dim strStatement As String

    strStatement = "EXEC " & pProc
    If Len(pArguments) > 0 Then
        strStatement = strStatement & " " & pArguments
    End If
    strStatement = strStatement & ";"
    Set rs = New ADODB.Recordset
    Set rs.ActiveConnection = pConnection
    rs.Source = strStatement
    rs.LockType = adLockOptimistic
    rs.CursorType = adOpenStatic
    rs.CursorLocation = adUseClient
    rs.Open
    Set GetDataFromSP = rs
End Function