For transactions with and without joins for database links 10.2.0.5+
- With 11g the hint “DRIVING SITE” will be ignored, generally
- Bug 13851819 : 11G DATABASE IGNORES DRIVING_SITE HINT
- –> Bug 13413837 : PREDICATE PUSHING AND VIEW MERGING NOT HAPPENING IN 188.8.131.52.0 TOGETHER.
- With 10.2.0.5++ there is a problem by generating plans of the remote query
- Behavior in 10g: remote sql sends, as expected, a filter with remote index usage
- Behavior in 11g: no filter –> remote full table scan
For both problems there is a patch:
- Bug 13057645 : PLAN OF A DISTRIBUTED QUERY IN 11G IS DIFFERENT FROM 10G
- Bug 11689699 : EXPLAIN PLAN CHANGED AFTER 10205 UPGRADE WITH CORRELATED SUB-QUERY OVER DB LINK
Both patches must be applied to get old behavior back.