Oracle Database 11g: “DRIVING_SITE” hint will be ignored


For transactions with and without joins for database links 10.2.0.5+

  1. 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 11.2.0.2.0 TOGETHER.
  2. 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:

  1. Bug 13057645 : PLAN OF A DISTRIBUTED QUERY IN 11G IS DIFFERENT FROM 10G
  2. 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.

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