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Home -> Community -> Usenet -> c.d.o.server -> Re: COMPATIBILITY flag
On Fri, 26 Mar 1999 00:32:07 GMT, Satar <satar_at_my-dejanews.com> wrote:
>There is no negative aspects of setting this parameter, your applications
>won't be hurt or molested. And yes, you can re-set it to whatever value you
>want.
Satar,
It is not so simple YES/NO answer on whether the COMPATIBLE parameter shold be downgraded without the negative implication on the applications.
For example, if your aplication uses multiple same-type triggers per table and you downgrade the COMPATIBLE below the 7.1, it will stop working.
Also, the implications of the downgrading can be rather complex, so there is a lot of things you have to perform before you reset the COMPATIBLE to the value that doesn't support the features your database is currently using (for eaxample read only tablespaces). Basicaly, the COMPATIBLE settings is recorded in *every* database file, that is in data files, redo log files, control files and also in the password file. The command ALTER DATABASE RESET COMPATIBILITY will reset the compatibility only in the headers of the datafiles, while you'll have to manualy recreate the control files and the password file and also clear all your log files. You'll also have to recreate your dictionary in steps, using supplied scripts (cat7???d.sql), depending how "low" you want to go.
Again, the whole process of downgrading the COMPATIBLE parameter can
be realy complex. It is described an explained in detail (about 6 full
pages!) in the "Technical Newsletter II/1997", a quarterly newsletter
of Swiss Customer Support. Unfortunately, it is not available online
AFAIK.
>Regards,
>Satar
>Oracle DBA/UNIX System Admin
>"Opinions are the result of the voices in my head only,
>and do not reflect my employer or Oracle Corporation."
HTH,
Jurij Modic <jmodic_at_src.si>
Certified Oracle7 DBA (OCP)