Microsoft Office 2000/Visual Basic Programmer's Guide

When Database Replication Should Not Be Used

Although database replication can solve many of the problems inherent in distributed-database processing, it is important to recognize that there are situations in which replication is less than ideal. You may not want to use replication if:

• There are large numbers of record updates at multiple replicas.   Solutions that require frequent updates of existing records in different replicas are likely to have more record conflicts than solutions that simply insert new records in a database. Record conflicts occur when any changes are made to the same record by users at different locations at the same time. Solutions with many record conflicts require more administrative time because the conflicts must be resolved manually. This is true even if different fields are updated within the same record.
  
  
• Data consistency is critical at all times.   Solutions that rely on information being correct at all times, such as funds transfers, airline reservations, and the tracking of package shipments, usually use a transaction method. Although transactions can be processed within a replica, there is no support for processing transactions across replicas. The information exchanged between replicas during synchronization is the result of the transaction, not the transaction itself.

For more information about replication, see the Microsoft Access and Microsoft Replication Manager Help files, and see the white paper "Database Replication in Microsoft Jet" (RepJet.doc), located in the ODETools\V9\Samples\OPG\Appendixes folder on the Office 2000 Developer CD-ROM.