Posted by jerry gitomer on 07/20/05 16:59
bettina@coaster.ch wrote:
> I read somewhere that to gain efficiency it is advisable to avoid the
> use of select. But they don't explain why or what to use instead. Is it
> true? I habe a problem of speed (better to say of NO SPEED) but I don't
> know if it has something to do with the use of select.
> Waht can I use instead?
>
Bettina,
I assume you are talking about using SELECT * vs SELECT
<column-name-list>. If that is so the correct answer is that it
doesn't make any significant difference. Most of the time in
database operations is spent accessing and reading data from the
disk drives -- not processing the data once it has been read.
(The difference is something like ten to one.)
The vast majority of the complaints about database performance
being too slow are the result of not having indexes, not using
the indexes that do exist, and failing to run the RDBMS admin
programs that analyze the data and update the index usage strategy.
HTH
Jerry
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