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From abr...@apache.org
Subject svn commit: r470943 - /db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/compile/OptimizerImpl.java
Date Fri, 03 Nov 2006 18:57:03 GMT
Author: abrown
Date: Fri Nov  3 10:57:02 2006
New Revision: 470943

URL: http://svn.apache.org/viewvc?view=rev&rev=470943
Log:
Test committer capabilities by making a small fix to comments
in OptimizerImpl.java

Modified:
    db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/compile/OptimizerImpl.java

Modified: db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/compile/OptimizerImpl.java
URL: http://svn.apache.org/viewvc/db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/compile/OptimizerImpl.java?view=diff&rev=470943&r1=470942&r2=470943
==============================================================================
--- db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/compile/OptimizerImpl.java (original)
+++ db/derby/code/trunk/java/engine/org/apache/derby/impl/sql/compile/OptimizerImpl.java Fri
Nov  3 10:57:02 2006
@@ -973,11 +973,14 @@
 				/*
 				** When we pull an Optimizable we need to go through and
 				** load whatever best path we found for that Optimizable
-				** with respect to _this_ OptimizerImpl.  An Optimizable
-				** can have different "best paths" for different Optimizer
-				** Impls if there are subqueries beneath it; we need to make
-				** sure that when we pull it, it's holding the best path as
-				** as we determined it to be for _us_.
+				** with respect to this OptimizerImpl.  The reason is that
+				** we could be pulling the Optimizable for the last time
+				** (before returning false), in which case we want it (the
+				** Optimizable) to be holding the best access path that it
+				** had at the time we found bestJoinOrder.  This ensures
+				** that the access path which is generated and executed for
+				** the Optimizable matches the the access path decisions
+				** made by this OptimizerImpl for the best join order.
 				**
 				** NOTE: We we only reload the best plan if it's necessary
 				** to do so--i.e. if the best plans aren't already loaded.



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