Re: Migrating from Ingres to Oracle

Michael Martin wrote:
> Has anyone migrated from Ingres to Oracle recently? Where there any major
> issues?
> What about migrating;
> . procedure/rules to PL/SQL
> . data types
> . indexes & key, foreign constraints etc
> . non ANSI SQL
> . embedded SQL/C
> . JDBC, ODBC
> . other third party products (tuxedo etc)
> . any other issues
>
> If you migrated, why did you go from Ingres to Oracle?
>
> Thanks
> Michael

 From my experience ... I've helped with a few but the most recent was some years ago ... you should plan on rewriting everything.

In Ingres you had one type of table ... in Oracle many and lookup tables should most likely be turned into IOTs (index organized tables). In Ingres you didn't have near the available index types you will now have so you need to determine, on a case-by-case basis whether B*Tree or Bitmap or Compressed or Function based, etc. indexes will give you what you paid for.

But there are plenty of questions that need to be answered.

1. How much data?
2. How long for the migration?
3. What is the customer expectation?
4. What Oracle expertise in your shop?

My first instinct would be to dump the data to ASCII files and reload it.

I'd go JDBC over ODBC given the choice and be sure to thoroughly learn about BULK COLLECT and FORALL statements. Stay away from cursor loops except in very specialized circumstances.

HTH

-- 
Daniel A. Morgan
http://www.psoug.org
damorgan_at_x.washington.edu
(replace x with u to respond)