Question

Scenario: We have an application that is using Oracle 10g and the latest version of ODP.net within an ASP.net application. We are utilizing the .ClientID WriteOnly property on the OracleConnection object to pass in a specific UserID to the database for auditing purposes. When Connection Pooling is disabled, this works perfectly.

When it is enabled, the first person who logs in (ex: USER1) updates a record and the MODIFIED_BY is USER1, but when a different user heads into the website after, thus grabbing the pooled connection, the MODIFIED_BY is still USER1 despite passing in USER2 to the ClientID.

Our database logic is as follows:

We persist a class in an ASP.net session that has our database connection logic in it. On the initial call, this is our constructor:

Public Sub New(ByVal connection As String, Optional ByVal oracleClientID As String = "")
        MyBase.New()
        _oracleConnection = New OracleConnection(connection)
        _clientID = oracleClientID
        End If
    End Sub

Here’s the gist of the code to open connection and close, dispose:

Try
    _OraCmd = New OracleCommand(command, _oracleConnection)
    With _OraCmd
        .BindByName = True
        .Parameters.Clear()
        .CommandType = CommandType.StoredProcedure
        _oracleConnection.Open()
            If _clientID <> "" Then _oracleConnection.ClientId = _clientID
        Dim OraDadpt As New OracleDataAdapter(_OraCmd)
            '' Logic to get data
        OraDadpt.Fill(ds)
    End With
Catch ex As Exception
    Throw ex
Finally

    ClearParameters()
    _OraCmd.Dispose()
    _oracleConnection.Close()
End Try

The thought is that since the connection is pooled, there is an assumed call to a LOGON Trigger that never happens and the Client Identifier is never set again. ORACLE’s documentation, however, states that the ClientID is used for exactly what we are trying to do.

Does anyone have any thoughts as to why the SYS_CONTEXT(‘USERENV’, ‘CLIENT_IDENTIFIER’) is not being set to a new USERID that is passed into the ClientID when connection pooling is used within our .NET application with ODP.net? Is this a database setting, a listener setting?

Update

We forwarded the issue to Oracle. In doing so, we had to create a small test app that mimicked the issue. When doing that, on my localhost — everything worked perfectly using Visual Studio’s built-in Cassini web server. With IIS, the issue occurs.

UPDATE

Determined that IIS wasn’t the problem. It was package variables not being cleared out due to connections that were pooled being re-used, in essence, what pooling is supposed to do. We solved this by using DBMS_SESSION.MODIFY_PACKAGE_STATE(DBMS_SESSION.REINITIALIZE).

Answer 1

Try using DBMS.Rest_Package before closing the connections.

The problem I think is with pooling turned on ODP is keeping the connection thus as each user opens and closes a connection with ODP, pooling is keeping the session package variables in memory; until the connection times out. However, since the time/out and re-establish of a connection from the database to the pool only occurs AFTER a connection is RETURNED to the pool, you’re operating with someone else’s session data.