Re: Dual - multiple rows

A funny little point about DUAL:

in 8.1.5 (if not sooner) there is a virtual object called x$dual - and when you run svrmgrl you can 'select * from dual' and find that the result is the same as 'select * from x$dual' SO LONG AS the database is started, or mounted but not open.

I wouldn't be 100% sure that any other 'dual' would be exactly the same as SYS.DUAL
(unless you had told me so): I recall a note in one of the earlier Oracle manuals stating that the database engine had special information that enabled it to know that DUAL was a table with a single row and act accordingly - in the days before CBO.

--

Jonathan Lewis
Yet another Oracle-related web site: http://www.jlcomp.demon.co.uk

Thomas Kyte wrote in message ...
>
>if you create your own application specific single row table -- it'll be
100%
>like dual.
>
Received on Mon Sep 06 1999 - 13:25:07 CDT