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Home -> Community -> Usenet -> c.d.o.misc -> Re: Dual - multiple rows
Norris wrote:
>
> May I know if there is any performance difference if I do not the SYS.DUAL
> and use my own dummy table?
>
> By the way, can I revoke the insert and delete rights on SYS.DUAL
> from all users to set the table readonly?
>
> 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
>
> --
> --
> http://www.washington.edu/pine/faq/
Yes it will be the same..
I've seen this done at sites, and then they put
check = 'X' and a unique key on the row to avoid 2 rows...but this simply masks the fact that somewhere in the scheme of things you have someone with powerful privs experimenting somewhere....Ugh! --
"Some days you're the pigeon, and some days you're the statue." Received on Mon Sep 06 1999 - 05:57:20 CDT
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