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From Rick Hillegas <Richard.Hille...@Sun.COM>
Subject Re: jira question
Date Wed, 03 Aug 2005 13:55:06 GMT
Thanks, Jeff. I agree. Recompiling these expressions can occur when we 
compile the triggering SELECT/UPDATE/INSERT statements. Compiling a 
SELECT/UPDATE/INSERT is a relatively heavyweight operation and I don't 
think anyone will notice a little extra time spent recompiling these 
expressions.

Cheers,
-Rick

Jeffrey Lichtman wrote:

>
>> The expression used for the generated column must be stored in the
>> data dictionary. Does derby serialize expressions? I was looking
>> around in the classes in impl/sq/compile (ValueNode and such) and
>> these classes don't seem to implement Formatable.
>
>
> It would be better to store the expressions as text, and to parse and 
> bind them when needed. I learned the hard way while working on the 
> internals of other database systems that storing internal data 
> structures in the data dictionary causes trouble when the structures 
> change. Also, it's useful for users to be able to look at the text of 
> their DDL statements.
>
>
>                        -        Jeff Lichtman
>                                 swazoo@rcn.com
>                                 Check out Swazoo Koolak's Web Jukebox at
>                                 http://swazoo.com/




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