[Building Sakai] (no subject)

[Adams, David]

On Mar 16, 2011, at 12:26 PM, Jennings, Michael wrote:
> Here at UNC-Chapel Hill we are trying to quickly make a decision on if we should go with MySQL for our Enterprise Database or use Oracle.
> Currently UNC-Chapel Hill is a Oracle shop and we are not running any MySQL databases at an enterprise level.  I would like to see what
> the pro’s and con’s of using each database would be, and see if there are any major hurdles with using Oracle that we will have to overcome.

Hey Mike,
At Virginia Tech we run Oracle, and as has been mentioned, several large schools also use Oracle, so the community support is there. However, in our experience we've found numerous small issues with Oracle support. Rarely anything approaching a blocker-type issue, but small problems that have to be specially addressed or worked around. I think this can be attributed to the fact that MySQL is a more common database for production deployments and on developers' PCs, MySQL is pretty much the only thing that is used. So you aren't going to run into problems with MySQL, but there will be little things wrong with Oracle. A few things we've run into:

 - Auto-generated Hibernate DDL for table creation once set blob-type fields to the wrong datatypes in Oracle, using the deprecated LONG and LONG RAW instead of CLOB and BLOB. Sakai works with these datatypes, but they are harder to work with directly, and given that they may be going away in a future version of Oracle, it's best to avoid them. Changing the datatype is possible, but you'll want to catch it immediately. This may have been addressed. See https://jira.sakaiproject.org/browse/SAK-16797 and https://jira.sakaiproject.org/browse/SAK-7977

- Oracle-specific performance problems in some less-popular tools, including SiteStats. I believe the SiteStats problem in particular has been addressed. See https://jira.sakaiproject.org/browse/STAT-200.

- Conversion files between Sakai versions are often less well tested on Oracle, and so column lengths may be different and indexes may be missing. We've run into this with every upgrade.

Search for "oracle" on http://jira.sakaiproject.org and you'll find other instances of this effect. A couple more examples of little problems we've run into:

  https://jira.sakaiproject.org/browse/SAM-1128
  https://jira.sakaiproject.org/browse/SAK-15910

Like I said, rarely are the problems major, but my impression is that these things don't sneak up on MySQL installs nearly as often. Add to that the fact that MySQL is just far far more well tested thanks to its near-universal use by developers, and I think for a school starting from scratch, MySQL is the better option. Obviously you have to weigh that against your available DBA expertise, but I think avoiding the headaches on the software side are worth a little more uncertainty on the DB side.

Just my two cents.

David Adams
Director, Learning Systems Integration and Support
Virginia Tech Learning Technologies