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From "Aakash Bordia" <bor...@gmail.com>
Subject questions about querytreenode and optimization
Date Wed, 11 Jul 2007 23:28:48 GMT
Hi, I am issuing a simple join query like:
select * from t1,t2 where t1.c1=t2.c1;

Here comes my novice questions(bear with me if some of these dont make
sense, trying to learn the compiler part):

1) I am not sure where to look for the accesspath(both base tables and
join),  as the values in AccessPathImpl (at join or PRN or base table level)
seem un-intuitive.

2) Also it seems we hang the Level2OptimizerImpl objects off of the base
table FromBaseTable, but I dont see it up in the tree anywhere. Is there a
reason for this?

Any other pointers for learning about the querytreenodes are appreciated !
Thanks
Aakash

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