Re: migrating from oracle 7.3.3 to 8.1.7 question

Did the export of a 4Gb 7.3.3 database on NT4 took 6 hrs? You can count 3 or 4 times as long for the import. Time needed for Migration is not directly related to the db size, more to the size of the dictionary.

With your 8.1.7 software there should be a documentation CD, containing all generic documentation in HTML and PDF format. In the group "Oracle8i server and SQL*Plus" you will find the book "Oracle8i Migration". Chapter 4 tells you all about the migration from Oracle7 using the Migration Utility. Check the NT specific release notes too for Windows specific actions (like the services that start the database).

I know the Migration Utility is not that much reliable. It may work for you. If possible I would use full export/import. Beside the problems with Migration Utility another argument is that the rowid format has changed. That means every block of all database files will be converted to Oracle8i format the first time it is touched, not during the Migration. I have no experience with it but I wonder what the impact is on performance, specially the first days/weeks after migration.

Some export/import advices:
1. make sure system and rollback tablespaces are large enough. System is much bigger in V8. The Migration book tells you about it. 2. import without indexes, use import indexfile=... to build a sql script that can create the indexes later (will not work for indexes build by constraints). The total time for doing it in 2 steps is much more shorter than letting import build all indexes (this is experience, if someone could explain me why?)
3. during import and index build, have a speciall (larger) value for init.ora parameter sort_area_size (like 2M or so) and make initial=next=sort_area_size+1 oracle block in the temporary tablespace to optimize the sort that's part of index creation. 4. look in the 7.3.3 database what objects you created as SYS (against Oracles advice) and what grants are given by SYS to others (you can't always prevent this; not standard things like grants to public or system). This is because the SYS schema is no part of the export (not a bug, that's by design because it contains the administration of the database which should not be imported to another database for obvious reasons).

michael.cooke <michael.cooke_at_tinyworld.co.uk> schreef in berichtnieuws 3ccaf85d_1_at_mk-nntp-1.news.uk.worldonline.com...
> Oracle 7.3.3 on NT4 sp6a to 8.1.7 on NT4 sp6a
> this is a 2fold operation moving 7.3.3 to a new server then in a few weeks
> time migrating to 8.1.7. I am testing the procedure at present and have
both
> oracle versions on the same server in different home directories. The
7.3.3
> dbase is up and running. I have tried a test migration using the gui
> migration tool in 8.1.7 and have a listener problem in tha it can't find
it.
> my question is is there a step by step migration guide covering each item
in
> turn and given that the dbase in question is only 4GB what sort of
timescale
> would be usual for this migration as i believe that in simple terms it is
> the file pointers that are updated along with a number of internal
> datadictionary changes. p.s. I did an export from 7.3 to 8.1.7 which
worked
> problem was it took about 6 hrs (I hope the migration is shorter.).
>
> thanks for any help
>
> Mick
>
>
Received on Sat Apr 27 2002 - 16:48:01 CDT