Вот письмо из моего архива за май 2003.
Прочитай с конца :)
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В продолжение темы - увидел недавно в CDI
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am sure there have been many posts for this issue in the past but I could
not find answer to my query below.
With Informix 9.21 on Linux 6.2 - How safe is (in terms of integrity of
system catalogue) to update systables
for changing owner of a table ? Also is this update for changing owner of a
table supported by IBM ?
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Dont even think about it. It is very unsafe.
If you want to change the owner, drop and recreate.
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It is definitely not supported by IFMX.

However I did it in the past and it worked without
further problems. You need to be user 'informix' to
update systables.owner.
You might also need to bounce the engine after this, because
the data dictionary cache is not up to date.

Remember to take a Level-0-Archvive before doing this and
also remember that you will get no support if it doesn't
work as you expect.
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It is fairly safe, but probably not supported by IBM.

The owner of a table has little meaning, unless you are using a MODE
ANSI database. If you really want to change it, then the supported
method is likely to be; unload, drop, recreate and load the table.
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I don't think that this has anything to do with
the update on systables.owner.
I tested the behaviour on Suse Linux 8.0 with IDS 9.30.UC3
and was able to change systables.owner and also to create
a role with the same name, for example:
update informix.systables
set owner = 'mytest'
where tabid > 99
and tabtype = 'T';
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"Igor Zavgorodny" <daugava@torba.com>; wrote in message
news:3ea3a8be$1@proxy...
> Vasyl Shulzhenko wrote:
> > "Журавлев Денис" <zhd@chspz.ru>; wrote in message
> >>в systables поле owner меняй.
> Подобный совет в 1995 году давал сам Leffler:
>
> "There is no official way to do it (apart from drop and recreate).
>
> Unofficially, suitably authorised users can update the Owner column in
> SysTables (and possibly SysIndexes, SysConstraints, etc.). Beware of
> how you revoke the privileges which were granted on the table by the
> old owner -- WITH GRANT OPTION can make this very tricky to do."
>
> >
> > Настоятельно не рекомендуется.
> > Можно нарваться на скрытые проблемы в будущем :(
> >
>
> Однако в 2002 году, тот же Leffler таких рекомендаций уже не дает:
>
> "There are feature requests asking for a change owner facility.
> However, changing the ownership of
> an object in a database is a fraught process - think about the
> inheritance of permissions, WITH
> GRANT OPTION, triggers, views, stored procedures, synonyms and so on.
> Also, who changes the
> ownership? The current owner, the new owner, 'informix', the DBA, any
> three of the four with a
> N-of-M-way encrypted key system? Non-trivial; I think 9.61 maybe a
> release or two early."
>
> Все это на фоне рассказов типа:
> "The last person I know who tried this then reached for his archive to
> restore since his database was unusable.
> Why would you want to change the owners? Use dbexport / dbimport or
> unload
> / drop / create / load."
>
> Так что Василий судя по всему прав.
> Regards, Igor.