Re: OK - Looking for the big Oracle guru brains

On 29 Aug 2001 06:20:35 -0700, pagesflames_at_usa.net (Dusan Bolek) wrote:

>However he wants to update just changed data and maybe the table in
>original database must be available all the time.

Yeah, still possible. But must use hardware. And the last copy of data in the target database.

Goes like this:

move the tables in question to their own tablespace. make it "transportable" to the target.
mirror the data files with the h/w.

at source:

at the required time, offline the tablespace (quiesce the database, whatever), break the mirror and online it again (one copy only). copy the second mirror image to the target system. glue the mirror back on again and keep going in main system.

at target:

add the tablespace from the copy of the "half" mirror. find the timestamps that have changed between the copied and the target tables. Use SQL or PL/SQL.
update the target tables with only those rows.

I think this would work? Conceptually, of course. There are details to be dealt with. Remember, no exp/imp is the requirement.

>Why he needs this ?

that's for him to answer.

>and What time he has for this operation ?
>

Let's do a "suppose":
could be a very small window, not enough to do an export? I've seen the above manipulation done with very large db's, to move daily stuff to daily reporting/summarizing system, while not affecting main production.

Cheers
Nuno Souto
nsouto_at_optushome.com.au.nospam Received on Wed Aug 29 2001 - 15:35:13 CEST