On Thu, 2007-04-05 at 11:39 +1000, Shaun Burriss wrote: > We are about to upgrade our DSpace installation from 1.3.1 to 1.4.1 and > also want to move our data from the Postgres database to an Oracle > database. What things should we be aware of when doing this data > migration? What are the steps involved?
Hi Shaun, To be honest, migrating to an Oracle database with 1.4.1 is probably not a good idea. At the moment, the 1.4.1 release has a number of known issues with it's Oracle support - fixes for which are currently being tested with a view to release as 1.4.2. Beyond that, the existing schema definition for Oracle uses VARCHAR2(2000) in place of Postgres' TEXT columns. This means that many fields - importantly, all the metadata values and license text - is limited to a maximum of 2000 characters. It is likely that this would cause problems with any attempted conversion. Again, one of the Oracle patches allows the use of CLOB columns, and a schema patch exists that makes use of them in the key fields (for example, metadata). This schema change isn't 100% perfect, as the browse tables need to retain the use of VARCHAR2 columns for ORDERing support - although it is highly unlikely that this would cause a problem in practise. > Also, should the migration to Oracle take place before or after our > DSpace update? Changing VARCHAR2 columns to CLOBs is a rather involved process, and my advice here would be to only start using Oracle with a DSpace that supports the use of CLOBs, and to start with a schema that uses CLOB columns where necessary/possible before you migrate the data in. In practise, I would therefore suggest that you upgrade to 1.4.1 on your Postgres database, and then migrate to Oracle after 1.4.2 is released. G -- Graham Triggs Technical Architect Open Repository Tel: +44 (0)20 7631 9942 Skype: grahamtriggs This email has been scanned by Postini. For more information please visit http://www.postini.com ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ DSpace-tech mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/dspace-tech
