Re: select * from dual;

Oracle has implemented an X$DUAL 'table' in recent versions of Oracle, which is the target for 'DUAL' when the database is not open.

Like (all) X$ table, this mapping into the SGA contains an address, index, and
instance id as well as the data column(s).

It's just unfortunate that Orale hasn't yet replaced all calls to dual with a redirect to x$dual when the database is open.

Jonathan Lewis
http://www.jlcomp.demon.co.uk

Host to The Co-Operative Oracle Users' FAQ http://www.jlcomp.demon.co.uk/faq/ind_faq.html

Author of:
Practical Oracle 8i: Building Efficient Databases

Screen saver or Life saver: http://www.ud.com Use spare CPU to assist in cancer research.

-----Original Message-----
To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com> Date: 25 September 2001 19:23

Gurus,

I get the following on

select * from dual; when the database is in the unmounted and the mounted state...

ADDR           INDX    INST_ID     D
--------      ----------  ----------      -
01653D38          0                1        X

and the normal

D
-
X when it is open. What does the other columns stand for ..

I am sure a lot of you know..

thanks in advance..

Anjan

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Author: Jonathan Lewis
  INET: jonathan_at_jlcomp.demon.co.uk

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