Background information
Let’s say I have two database servers, both SQL Server 2008.
One is in my LAN (ServerLocal), the other one is on a remote hosting environment (ServerRemote).
I have created a database on ServerLocal and have an exact copy of that database on ServerRemote. The database on ServerRemote is part of a web application and I would like to keep it’s data up-to-date with the data in the database ServerLocal.
ServerLocal is able to communicate with ServerRemote, this is one-way traffic. Communication from ServerRemote to ServerLocal isn’t available.
Current solution
I thought it would be a nice solution to use replication. So I’ve made ServerLocal a publisher and subscriptions are pushed to the ServerRemote. This works fine, when a snapshot is transfered to ServerRemote the existing data will be purged and the ServerRemote database is once again an exact replica of the database on ServerLocal.
The problem
Records that exist on ServerRemote that don’t exist on ServerLocal are removed. This doesn’t matter for most of my tables but in some of my tables I’d like to keep the existing data (aspnet_users for instance), and update the records if necessary.
What kind of replication fits my problem?
Option C: Transactional replication.
I’ve done this before where you have data in a subscription database and don’t want it overwritten by the snapshot. You can set your initial snapshot to not delete the existing records and either don’t create the records that are in the publisher (assume they are there) or create the records that are in the publisher (assume they are not there).
Take a look at what would be correct for your situation or leave a comment with more details on how you get your data in the subscriber originally. I’m not too familiar with aspnet_users and what that is. Transactional replication only helps if you don’t want the data in the subscriber back at the publisher. If you want that you’ll have to do merge replication.