RDOConnectMaster provides automatic/intelligent connection control to your Access or SQL Server databases. This means you can use the same code to interface with either database server. We take advantage of this to shorten our development activities, by developing with Access and deploying with SQL Server. The class automatically ensures that a database connection is made just once for any given database session. This means you can code each database function as a stand-alone unit that opens a connection, does its work, and then closes the connection (encapsulation at its finest). Then, when all your functions are used together, multiple (quite wasteful, excess) connections are avoided. What does this mean for your applications? When we started using RDOConnectMaster, our network access overhead dropped by over 50%. The class builds its own DSN-less connect string to your database. This avoids costly Registry searches on the client machine. For this specific implementation, we chose to use lean and mean Remote Data Objects; resulting in the most efficient possible access to the database. But the methods used will work equally well for ADO or DAO with minor changes to the connect string and procedures called. To see sample use of RDOConnectMaster and its full interface definition, scroll down.

dim oSigDb as RDOConnectMaster             'declare our object
dim Sigdb as rdoConnection                 'declare connection object
  Set oSigDb = New RDOConnectMaster        'initialize our object
  oSigDb.Srvr = lSignatureServer           'set database server name
  oSigDb.DataBaseName = lSignatureDatabase 'set database name
  oSigDb.UID = lSignatureUser              'provide a user name
  oSigDb.PWD = SigPassword                 'provide a password
  If oSigDb.dbOpen(OpenModes.ReadOnly, Sigdb) Then 'open connection
    Sql = "SELECT Unit,EmpNo,EmpName,UserId,DollarLimit,Img FROM " + _
          "Signatures WHERE ... "
    Set rs = Sigdb.OpenResultset(Sql, rdOpenKeyset, rdConcurRowVer) 
    'get the recordset
.
.{other processing}
.
    Call oSigDb.dbClose(Sigdb)             'close the connection
  Else                                     'problem with the open
    lstatus = FormatError(SubName, "Could not open "+oSigDb.DataBaseName)
  End If

Here is the interface definition for the RDOConnectionMaster Class. dbOpen supports both SQL Server and Access databases. If the connection is for an Access database, set DataBaseName to the fully qualified name of the database file; otherwise set it to the SQL Server database name and set Srvr to the name of the server.

Public Enum OpenMode ReadOnly = True 'dbOpen argument, connection is read-only ReadWrite = False 'dbOpen argument, connection is read/write End Enum Public Property Get Connect() As String 'Return Connect string Public Property Get DataBaseName() As String 'Return name of database Public Property Let DataBaseName(ByVal NewDataBaseName As String) ' Set database name Public Sub dbClose(db As rdoConnection) 'Close connection db Public Function dbOpen(rw As OpenMode, db As rdoConnection) As Boolean ' open connection db according to OpenMode Public Property Get OpenDepth() As Integer ' Return nesting level of opens Public Property Get OpenTime() As Date ' Return time connection was opened Public Property Get PWD() As String 'Return database password Public Property Let PWD(ByVal NewPWD As String) 'Set database password Public Property Get Srvr() As String ' Return name of database server Public Property Let Srvr(ByVal NewSrvr As String) ' Set database server name Public Property Get Time() As Long ' Return how long connection was open Public Property Get UID() As String 'Return user ID Public Property Let UID(ByVal NewUID As String) 'Set user ID Public Property Get WSID() As String 'Return work station ID Public Property Let WSID(ByVal NewWSID As String) 'Set workstation Id Public Property Get Error() As String ' Get text of last error. Use clears text