Oracle7 Server Distributed Systems Volume II: Replicated Data

Advanced Replication Compatibility Between Release 7.3 and Earlier Releases

The following are compatibility issues between Release 7.3 and earlier releases:

Coexistence of pre-Release 7.3 master sites and Release 7.3 master sites is permitted. You need to have a Release 7.3 master definition site to use new Release 7.3 features.

Two-phased generation of replication support is not supported in pre-Release 7.3 compatibility mode.

Replication behaves exactly as it would in a pre-7.3 release when COMPATIBILITY is set to a pre-Release 7.3 value.

Many existing replication administration requests have been modified to include additional fields to support new Release 7.3 functionality. Release 7.3 sites will process requests with the new fields. Pre-Release 7.3 masters will ignore the new fields and process requests normally. Listed in Table 13 - 33 are RepCatLog requests that are new to Release 7.3:

Requests	Comments
GENERATE_SUPPORT_PHASE1 and GENERATE_SUPPORT_PHASE2	A Release 7.3 master definition site will send out LOG_REQUEST_GEN_SUPPORT_PHASE1 and LOG_REQUEST_GEN_SUPPORT_PHASE2 requests only to Release 7.3 master sites. Remote pre-Release 7.3 master sites will only receive GENERATE_REPLICATION_ SUPPORT requests. These requests are only sent to Release 7.3 master sites that have the COMPATIBLE parameter set to 7.3.0 or higher.
ALTER_MASTER_ PROPAGATION	This request is only sent to Release 7.3 master sites that have the COMPATIBLE parameter set to 7.3.0 or higher.
ADD_MASTER_DATABASE	The new "overloaded" version of this request is only used at Release 7.3 master definition sites (similar to the already overloaded version used only at master definition site sites in pre-Release 7.3).

Table 13 - 33. New RepCatLog Requests in Release 7.3

The replication administration requests that require regeneration of all replication triggers at all master sites, for example, ADD_MASTER_DATABASE, will check for pre-Release 7.3-compatible triggers at the master definition site and regenerate these triggers as well.

Pre-Release 7.3 snapshot sites will attempt to copy triggers from their master sites. Release 7.3 triggers are incompatible with pre-Release 7.3 triggers. Therefore, DBAs can optionally generate pre-Release 7.3-compatible triggers at Release 7.3 master sites for the pre-Release 7.3 snapshots to copy (set GEN_REP2_TRIGGER to TRUE when calling DBMS_REPCAT.GENERATE_REPLICATION_SUPPORT()). The generated pre-Release 7.3-compatible triggers are disabled at the master sites and are not used at master sites.