Re: ALter table move on IOT - TOP

"Robert" <cookie - remove - @tref.nl> wrote in message news:bqiuo6$974$1_at_reader11.wxs.nl...
> Hi all,
>
>
> I have an 8.1.7.4 DB.
> The database holds a schema for a specific application.
> I recently inherited the administration off the instance.
> The guy who used to do it quit the job.
>
> I saw he used some IOT table's (i'm not sure why, but that's another
> question).

Because they are brilliant. Well, OK... they were awful in 8.0, passing useful in 8i and are brilliant in 9i. But that's evolution for you.

Any table that is primarily accessed by primary key should be investigated to see whether IOT'ing them would be a good idea. So long as there aren't 58 additional unique constraints on the thing, then quite likely, IOT treatment will be of benefit. You also want to avoid IOT'ing tables that need bitmap indexes (because in 8i that's impossible, and in 9i it's a palaver). There are one or two other restrictions that might be show-stoppers, too (think partitioning, log miner etc).

Not that this is any sort of recommendation, you understand: but Microsoft's SQL Server uses the equivalent of IOTs *by default* for any table that has a primary ley declared on it (they call them 'clustered indexes' IIRC)... which kind of gives you a clue.

Regards
HJR Received on Wed Dec 03 2003 - 12:38:49 CST