The Database Extraction utility

You can access the remote database extraction utility in the following ways:

From Sybase Central, for interactive use.

From the system command prompt, using the ssxtract or dbxtract utilities. This is useful for incorporating into batch or command files.

ssxtract is the extraction utility for Adaptive Server Enterprise, dbxtract is the extraction utility for Adaptive Server Anywhere.

By default, the extraction utility runs at isolation level zero. If you are extracting a database from an active server, you should run it at isolation level 3 (see “Extraction utility options” on page 306 ) to ensure that data in the extracted database is consistent with data on the server. Running at isolation level 3 may hamper others’ turnaround time on the server because of the large number of locks required. It is recommended that you run the extraction utility when the server is not busy, or run it against a copy of the database (see “Designing an efficient extraction procedure” on page 193 ).

Objects owned by dbo The dbo user ID owns a set of Adaptive Server Enterprise-compatible system objects in an Adaptive Server Anywhere database.

For Adaptive Server Anywhere, the extraction utility does not unload the objects created for the dbo user ID during database creation. Changes made to these objects, such as redefining a system procedure, are lost when the data is unloaded. Any objects created by the dbo user ID since the initialization of the database are unloaded by the Extraction utility, and so these objects are preserved.

Extracting a remote database in Sybase Central

Running the extraction utility from Sybase Central carries out the following tasks related to creating and synchronizing SQL Remote subscriptions:

Creates a command file to build a remote database containing a copy of the data in a specified publication.

Creates the necessary SQL Remote objects, such as message types, publisher and remote user IDs, publication and subscription, for the remote database to receive messages from and send messages to the consolidated database.

Starts the subscription at both the consolidated and remote databases.

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Sybase DC38133-01-0902-01 manual Database Extraction utility, Extracting a remote database in Sybase Central