Re: Estimate a query time

suri wrote:
> yes, you get the point.

I guess if I would have known that was your point, then I wouldn't have even offered up the PROFILE information as it bears no relevance to what you seek.

> Of course I can go and check the passed
> parameters which are quite cumbersome and I thought that there is a
> generic way in Oracle to estimate the query beforehand.

Unfortunately, there is no way to provide this estimate before the fact. Oracle does not have that functionality.

Even querying V$SESSION_LONGOPS for the TIME_REMAINING is not always accurate. Oracle knows it has XXX blocks to process for that query and it too YY time to process ZZZ of XXX so far. It uses simple mathematics to extrapolate the TIME_REMAINING. But other factors can throw the TIME_REMAINING value off. For instance, another user performing another long I/O operation on the same disk can now cause disk contention, which can increase the real time remaining. Oracle does try to compensate this by reevaluating the time remaining, but its not always perfect.

HTH,
Brian

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Brian Peasland
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