Comparing replication methods

Table 3-2 compares sp_reptostandby and sp_setreptable, detailing how each copies information to the standby database. Many of these issues are discussed in detail later in the chapter.

Table 3-2: Comparison of table replication methods

sp_reptostandby

sp_setreptable

Copies all user tables to the standby database.

Lets you choose which user tables are copied to the standby database.

Allows replication of DML commands and supported DDL commands and system procedures. Supported DDL operations are listed in “Supported DDL commands and system procedures”.

Allows replication of DML commands executed on marked tables.

NoteSupported DDL operations can be replicated for an isql sessions. Refer to “Forcing replication of DDL commands to the standby database” for more information.

Does not copy DML and DDL operations to replicate databases.

If the warm standby application also copies data to a replicate database, you must mark tables to be copied to the replicate database with sp_setreptable.

Copies DML operations to standby and replicate databases.

Copies execution of the truncate table command to the standby database. No subscription is needed.

NoteYou can enable or disable replication of truncate table to standby databases with the alter logical connection command. See “Replicating truncate table to standby databases” for more information.

If you use Adaptive Server databases, copies execution of truncate table to standby databases. No subscription is needed.

Replication Server uses table name and table owner information to identify a table at the standby database.

If you include the owner_on keywords when you mark a table for replication to the warm standby, Replication Server uses table name and table owner information to identify a table at the standby database.

If you include the owner_off keywords when you mark a table for replication to the warm standby, Replication Server uses the table name and “dbo” to identify a table at the standby database.

By default, text, unitext, image, and rawobject columns are copied to the standby database only if changed.

If you mark the database tables with sp_reptostandby and sp_setreptable, text, unitext, image, and rawobject data may be treated in a different way. Refer to “Replicating text, unitext, image, and rawobject data” for more information.

By default, text, unitext, and image columns are always copied to the standby database.

If you set the replication status with sp_setrepcol, text, unitext, image, and rawobject columns are treated as marked: always_replicate, replicate_if_changed, or do_not_replicate.

The easiest method to use when the active and standby databases are identical. Replication definitions are not required, but can be used to optimize performance.

Replication definitions are not required, but can be used to optimize performance.