Sybase DC38133-01-0902-01 Stable queue, Administering SQL Remote for Adaptive Server Enterprise

Models: DC38133-01-0902-01

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Chapter 12. Administering SQL Remote for Adaptive Server

Enterprise

Message Agent must be run to reclaim log space

The Message Agent must be run frequently enough to prevent the transac- tion log from running out of space. The dump transaction command does not reclaim space from pages after the truncation point.

Replication Server and Using SQL Remote on an Adaptive Server Enterprise database participating

SQL Remotein a Replication Server setup may involve other considerations. If your database has a replication agent (LTM) running against it, then you need to use the SQL Remote Open Server as an additional component. Adaptive Server Enterprise databases have replication agents running against them in the following circumstances:

The database is participating in a Replication Server setup as a primary database, or

The database is participating in a Replication Server setup and is using asynchronous procedure calls.

If the database is participating in a Replication Server setup as a replicate site, and no asynchronous procedure calls are being used, there is no need for the SQL Remote Open Server.

For more information about the SQL Remote Open Server, see “Using SQL Remote with Replication Server” on page 277 .

The stable queue

The Message Agent for Adaptive Server Enterprise uses a stable queue to hold transactions until they can be deleted. A stable queue is a pair of database tables that hold messages that may still be needed by the replication system.

SQL Remote for Adaptive Server Anywhere does not use a stable queue.

Stable queue not identical to Replication Server stable queue

Sybase Replication Server also uses stable queues as storage areas for replication messages. The Replication Server and SQL Remote stable queues perform similar functions, but are not the same thing.

Stable queue location The stable queue may be kept in the same database as the tables being replicated, or in a different database. Keeping the stable queue in a separate database complicates the backup and recovery plan, but can improve performance by putting the stable queue workload on separate devices and/or a separate Adaptive Server Enterprise server.

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Sybase DC38133-01-0902-01 manual Stable queue, Administering SQL Remote for Adaptive Server Enterprise