Re: Flamewar object databases vs. relational databases

Todd Gillespie wrote:
> : You use the "_seq.nextval from dual" approach, that ORACLE recommends in
 the
> : documentation. I was trying to point out that insertion of joined
 multiple
> : rows requires data to go back and forth between client and server. In
 your
> : example this does happen. This is where quite a bit of performance is
 lost.
>
> Bah. That's one of the smallest possible queries. You also don't need to
> do it at all if you use _seq.currval on the subsequent rows.
> Not having subselects - that's where major lossage on the wire occurs.

The execution time of the query does not cause the performance deficit. The transferral to the client is where the time is waisted.

> : You could use select(max) or select _seq.curval in your insertion
 statement
> : otherwise.
>
> Not sure how that relates to multiple-users. The results are isolated
> from other clients until commit(); who cares what id method you choose?

select(max) is not isolated, _seq.curval is. curval is ORACLE-specific and not available on other industrial standard databases.

Kind regards,
Carl

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Carl Rosenberger
db4o - database for objects - http://www.db4o.com