Re: Count(*) not doing a FTS??

Did your instructor say this with a straight face? There's no such voodoo as a rowcount in a segment header. The two ways you can do it are a FTS or fast full scan of a not null index. There are other more exotic ways (materialized view) but nothing involving the segment header, that I know of. In this case providing a counter-example is actually easier, have the instructor provide an execution plan where that shows something other than a FTS or index FFS.

S-

On Thu, 2 Sep 2004, rjamya wrote:

> I am sitting in a class and instructor told us that count(*) reads
> rowcount from segment header in some (or most?) cases rather than
> doign the good ol' FTS. He can't remember exact details, so this email
> ....
>
> is it true? Which version was this introduced? Someone has a
> reproducible test case?
>
> Thanks in advance
> Raj
> ------------------------------
> ---
> To unsubscribe - mailto:oracle-l-request_at_freelists.org&subject=unsubscribe
> To read recent messages - http://freelists.org/archives/oracle-l/09-2004
>

---
To unsubscribe - mailto:oracle-l-request_at_freelists.org&subject=unsubscribe 
To read recent messages - http://freelists.org/archives/oracle-l/09-2004