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From Stanislav Gromov <gro...@relex.ru>
Subject Page Allocating
Date Tue, 26 Apr 2005 13:43:42 GMT
I have an question.

As I can understand, Derby don't load whole file(table) in the memory.
It reads pages from it.
So. Question. How does it allocates Pages?
For Example, this SQL Statement
SELECT *
FROM TABLE1, TABLE2
WHERE TABLE1.ID = TABLE2.ID

How does it works?
Does Derby try to read both files (one for TABLE1 and one for TABLE2) 
entirely (all Pages),
and then make Result?
Or how?

Or this Example.
SELECT * FROM TABLE1 WHERE TABLE1.ID=3

Does Derby try to read file entirely (page by page)?
and then make Result?
Or it allocate only needed pages and read only them?

ps.Sorry for my bad English... ;-)

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