David Hallberg

Purges Help Minimize Database Growth

Millennium® uses the Oracle database as its main repository of information, which includes data that you may only want to keep for a period of time. This period may be one day or 365 days, but what is important is to delete the data as soon as you can to keep your database as trim as you can.

Millennium has many purges to delete rows from application tables that are not designed for long-term storage. Generally, a 2007.18 client has 147 active purge templates. Without all of them running, you are going to experience a couple of side effects. The first is general database growth. You want to control growth where you can so that backups run as fast as possible and, if you have to recover the database, recovery times are shortened. A second side effect also relates to database size. Depending on the way the applications are written and the indexing on the tables being purged, if you get too large you can have stability and performance issues within the applications. Generally, the Open Engine and old MDI applications are the most susceptible.

I realize that my advice to configure all of the purges for your Millennium version goes against what many of you believe or have been told by consultants — that you only want purges for the applications you are using. Here’s why I disagree. The system experiences no degradation when it runs a purge for an unused application. If you try to purge a table that has no data in it, the purge script looks for qualifying rows and says, “No rows match,” and then the process moves on to the next purge. There is no harm to the system and no performance impact to users. If, however, you decide at some point to implement that application, the purge will already be set up, saving a step in the activation process.

You should set up all of the purges to run at least once each day. After any Millennium upgrade, look for new purges to configure for optimal performance of Millennium and to make database recovery as rapid as possible.

To learn how to configure and run purges, click here.

Prognosis: Purging unused data daily helps keep the system as trim and spry as possible.