Re: Oracle non-DBA FAQ 0.4
From: L. Carl Pedersen <carl.pedersen_at_dartmouth.edu>
Date: Thu, 27 May 1993 16:51:43 GMT
Message-ID: <carl.pedersen-270593123649_at_kip-sn-67.dartmouth.edu>
Date: Thu, 27 May 1993 16:51:43 GMT
Message-ID: <carl.pedersen-270593123649_at_kip-sn-67.dartmouth.edu>
In article <dtb.738347042_at_otto>, dtb_at_otto.bf.rmit.oz.au (David Bath) wrote:
>
>
> ORACLE NON-DBA FAQ (Frequently Asked Questions) - Version 0.3
> -----------------------------------------------------------------
>
[stuff omitted]
> 2.14. What is ROWNUM good for ?
[stuff omitted]
> The other good thing about ROWNUM is that it is the quickest way to > reference a particular row in a table, providing that no table > reorganization happens in the meantime.
ACK! This is wrong. You are confusing ROWNUM and ROWID. In fact, since ROWNUM is not assigned until after the rest of the WHERE clause is executed, the only *single* row you can select using ROWNUM is the first. The following will never return any rows, no matter what is in T:
select * from t where rownum = 2; Received on Thu May 27 1993 - 18:51:43 CEST