Re: Migrating 8i database to 9i

Yup. Migration is very well documented in all Oracle versions. There's a migration executable which you run to generate a special sort of control file, but you have to do a fair bit of manual manipulation of environment variables yourself, at precisely the right time (the doco lays it all out, step by step). You are also responsible for things like copying your own init.ora, password files etc. And you have to edit your own init.ora to remove any de-supported parameters. You then have to issue a SQL command to do the actual conversion, followed by a resetlogs. You then have to do some tidying up (a user account gets dropped, for example). And then you have to run a fistful of sql scripts, but the precise ones you need to run depends entirely on what special features of the database you are using already, what ones you intend to use, and what specific version you are migrating from. It is all spelled out very clearly.

There are alternatives. Installing 9i, the installation usually detects existing earlier-version databases, and proposes to migrate them automatically. Never tried it myself, and wouldn't know how reliable it is.

Both methods are 'in-place' migrations, meaning that the database is out of action for the duration, and if anything goes wrong, you could be in deep doo-doo. Hence the doco's stern warning to backup before you start! A lot of people therefore prefer simply to install 9i, create a fresh (and empty) database manually, and then use boring old export (version 7) and import (version 9i) to transfer the data. The 7 database is still there to fall back to if anything goes pear-shaped, and doesn't have to be shutdown for the duration. On the other hand, exporting and importing a "large" database is going to take for ever, export/import are not the world's most reliable utilities, and an awful lot can go wrong. So I never recommend that particular route myself.

But it's horses and courses, as ever.

Regards
HJR

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"Don Seiler" <don.seiler_at_cellcom.com> wrote in message
news:d9bd959f.0203190647.51ae3599_at_posting.google.com...


> At the risk of getting similar treatment:

>

> I "need" to upgrade an Oracle 7.3.4 database (VERY large, if that

> matters) to Oracle 9i.  This is further complicated by the desire to

> migrate from HP-UX (on HP :p) to Linux (on x86).

>

> Shall I assume that necessary instructions for such a migration are

> included with the Oracle 9i .gz collections?

>

> Don.

>

> vslabs_at_onwe.co.za (Billy Verreynne) wrote in message

news:<3c909cd0.114756092_at_news.saix.net>...


> > "JK Nidhi" <jk_nidhi_at_hotmail.com> wrote:

> >

> > >Can someone suggest the best way to migrate an oracle 8i database to 9i

> >

> > Yes sir.  You start at Step 1.

> >

> > 1. RTFM.