Re: Using Indexes

From: Denny Koovakattu <denny_vk_at_my-dejanews.com>
Date: Mon, 01 Mar 1999 20:37:20 GMT
Message-ID: <7betpv$4ie$1@nnrp1.dejanews.com>

In this case there is no limiting condition given. If you want to force it to use the index try

SELECT IDCODE FROM PERSONEL
WHERE IDCODE > <some very low value>
ORDER BY IDCODE; Since it's already sorted it will only use the index. There's no need for the sort step. But for the same query if you are giving an

ORDER BY IDCODE DESC then it use the index and also do the sorting.

Denny

In article <36DAC9AF.6A9E74C9_at_yahoo.com>, DelphiDev <DelphiDev_at_yahoo.com> wrote:
> I have submitted the following statements to SQL Plus 3.3 on Oracle 7.0:
>
> SELECT IDCODE FROM PERSONEL ORDER BY IDCODE;
>
> This query takes a fair amount of time. I then index it and run the
> query again:
>
> CREATE INDEX IDCODEINDEX ON PERSONEL(IDCODE)
> SELECT IDCODE FROM PERSONEL ORDER BY IDCODE;
>
> The query seems to take the same amount of time to "Order" the records
> before actually printing them. I assume that if a index is present then
> Oracle will take advantage of it. This doesn't seem to be the case.
> Could someone explain this?
>
> Thanks, Stan.
>
>

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