Re: Dual - multiple rows

A copy of this was sent to Norris <johnnie_at_cooper.com.hk> (if that email address didn't require changing) On 6 Sep 1999 13:37:30 GMT, you wrote:

>May I know if there is any performance difference if I do not the SYS.DUAL
>and use my own dummy table?
>

if you create your own application specific single row table -- it'll be 100% like dual.

>By the way, can I revoke the insert and delete rights on SYS.DUAL
>from all users to set the table readonly?
>

your dba's have lots of "ANY TABLE" (eg: select any table, insert any table) type of privs. it will not affect people with powerful privs.

normal users only have select on dual so normally they will not be able to insert/delete from dual, only select it. its the people with the power that are the problem.

>Thomas Kyte <tkyte_at_us.oracle.com> wrote:
>: A copy of this was sent to Norris <johnnie_at_cooper.com.hk>
>: (if that email address didn't require changing)
>: On 6 Sep 1999 03:40:31 GMT, you wrote:
>
>:>Thomas Kyte <tkyte_at_us.oracle.com> wrote:
>:>: A copy of this was sent to Norris <johnnie_at_cooper.com.hk>
>:>: (if that email address didn't require changing)
>:>: On 4 Sep 1999 03:53:13 GMT, you wrote:
>:>
>
>: [snip]
>
>:>
>:>: It will also put an index on DUAL which *may* mess up query plans in some
>:>: unforseen way (so it is not recommended).
>:>
>:>If a table has only one record with unique index, I think most RDBMS query
>:>optimizer wouldn't use that index in the query plan unless we have
>:>special instruction.
>:>
>
>: as I said "some unforseen way". I haven't done it. I haven't tested it. I
>: have no idea what sort of side effects it might have here and there with
>: different releases. Rather then putting the constraints on dual (unsupported
>: would probably be the quote support would use) -- I'd rather watch my DBA's.
>
>:>
>:>: The best way to ensure dual has 1 row is to keep control of who has DBA and make
>:>: sure they are competent for the job.
>:>
>:>Can we add audit trail on the dual so that we can know which DBA have
>:>modified the dual?
>:>
>
>: well, as long as your dba's dont use INTERNAL or SYS (which are never audited)
>: and each have their own userids, this would probably work.
>
>:>
>:>:>
>
>
>: --
>: See http://govt.us.oracle.com/~tkyte/ for my columns 'Digging-in to Oracle8i'...
>: Current article is "Part I of V, Autonomous Transactions" updated June 21'st
>:
>: Thomas Kyte tkyte_at_us.oracle.com
>: Oracle Service Industries Reston, VA USA
>
>: Opinions are mine and do not necessarily reflect those of Oracle Corporation
>
>--

--
See http://govt.us.oracle.com/~tkyte/ for my columns 'Digging-in to Oracle8i'... Current article is "Part I of V, Autonomous Transactions" updated June 21'st  

Thomas Kyte                   tkyte_at_us.oracle.com
Oracle Service Industries     Reston, VA   USA

Opinions are mine and do not necessarily reflect those of Oracle Corporation Received on Mon Sep 06 1999 - 12:29:03 CDT