[eclipselink-dev] SVN trunk Commit: Bug# 301599 - avoid m-m join, 228428

[James Sutherland <JAMES.SUTHERLAND@xxxxxxxxxx>]

SVN trunk Commit: Bug# 301599 - avoid m-m join

 

https://bugs.eclipse.org/bugs/show_bug.cgi?id=301599

 

Avoid join from m-m join table to target table when only the id is compared.

 

Code review: Andrei

 

Changes:

- Optimize join in RelationExpression normalize for m-m id comparison, also avoid opt for 1-1 if a custom query mapping.

- Some micro opt, remvoed some dead code.

- Made ReadObjectQuery cache check only check the local unit of work cache, as the session cache is checked separately and was being checked twice.

- Changed AbstractDirectMapping to check for null and equality first to handle serialized objects correctly.

- Changed AbstractTransformationMapping

-- use List instead of Vector

-- fixed usage of indirection

-- mutable checks

-- compare byte arrays correctly

-- some cleanup, overrides

-- Avoid conforming in queries if the unit of work is empty.

-- Test for m-m join optimization.