replication.

 

Both databases

Messages must be sent both ways, so not only does a remote database

subscribe

subscribe to a publication created at the consolidated database, but the

 

consolidated database must subscribe to a corresponding publication created

 

at the remote database.

 

 

Data updates and

 

receipt confirmations

 

Publish

Subscribe

Data updates and receipt confirmations

Consolidated Subscribe

Publish

Remote

database

 

database

When remote database users modify their own copies of the data, their changes are replicated to the consolidated database. When the messages containing the changes are applied at the consolidated database the changes become part of the consolidated database’s publication, and are included in the next round of updates to all remote sites (except the one it came from). In this way, replication from remote site to remote site takes place via the consolidated database.

Synchronizing a remote When a subscription is initially set up, the two databases must be brought to

databasea state where they both have the same set of information, ready to start replication. This process of setting up a remote database to be consistent with the consolidated database is called synchronization. Synchronization can be carried out manually, but the database extraction utility automates the process. You can run the Extraction utility as a command-line utility or, if you are using an Adaptive Server Anywhere consolidated database, from Sybase Central.

The appropriate publication and subscription are created automatically at remote databases when you use the SQL Remote database extraction utility to create a remote database.

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Sybase DC38133-01-0902-01 manual Replication, At the remote database