How to reduce a database

Hi list,

I have an openNMS server that uses a Postgres database. For those who are not familiar, openNMS is an open source network management product.

Anyway, the openNMS database is very large now, more than 25GB (considering all tables) and I am starting to have disk space issues. The openNMS product has a vacuumdb procedure that runs every 24 hours and reads a vacuumd-configuration.xml file for parameters on what to do.

The problem is that this process is not reducing the database size. What I need to do is to delete some records based on timestamp fileds or something like that. I don't know how to do it though.

Can you guys help me with some command line examples?

There is this table, called EVENTS, that have the following structure:

 eventid                 | integer                     | not null
 eventuei                | character varying(256)      | not null
 nodeid                  | integer                     |
 eventtime               | timestamp without time zone | not null
 eventhost               | character varying(256)      |
 eventsource             | character varying(128)      | not null
 ipaddr                  | character varying(16)       |
 eventdpname             | character varying(12)       | not null
 eventsnmphost           | character varying(256)      |
 serviceid               | integer                     |
 eventsnmp               | character varying(256)      |
 eventparms              | text                        |
 eventcreatetime         | timestamp without time zone | not null
 eventdescr              | character varying(4000)     |
 eventloggroup           | character varying(32)       |
 eventlogmsg             | character varying(256)      |
 eventseverity           | integer                     | not null
 eventpathoutage         | character varying(1024)     |
 eventcorrelation        | character varying(1024)     |
 eventsuppressedcount    | integer                     |
 eventoperinstruct       | character varying(1024)     |
 eventautoaction         | character varying(256)      |
 eventoperaction         | character varying(256)      |
 eventoperactionmenutext | character varying(64)       |
 eventnotification       | character varying(128)      |
 eventtticket            | character varying(128)      |
 eventtticketstate       | integer                     |
 eventforward            | character varying(256)      |
 eventmouseovertext      | character varying(64)       |
 eventlog                | character(1)                | not null
 eventdisplay            | character(1)                | not null
 eventackuser            | character varying(256)      |
 eventacktime            | timestamp without time zone |

I was thinking about using a DELETE FROM EVENTS WHERE  eventtime = <some point in time>......but I am kind of worried on what this could cause on other tables, if there is some relations between them or something.....

Here is the vacuumd-configuration.xml file:

<VacuumdConfiguration period="86400000" >
    <statement><!-- this deletes all the nodes that have been marked as deleted - it relies on cascading deletes --> DELETE FROM node       WHERE node.nodeType = 'D'; </statement>
    <statement><!-- this deletes all the interfaces that have been marked as deleted - it relies on cascading deletes --> DELETE FROM       ipInterface WHERE ipInterface.isManaged = 'D'; </statement>
    <statement><!-- this deletes all the services that have been marked as deleted - it relies on cascading deletes --> DELETE FROM if      Services WHERE ifServices.status = 'D'; </statement>
    <statement><!-- this deletes any events that are not associated with outages - Thanks to Chris Fedde for this --> DELETE FROM even      ts WHERE NOT EXISTS (SELECT svclosteventid FROM outages WHERE svclosteventid = events.eventid UNION SELECT svcregainedeventid FROM out      ages WHERE svcregainedeventid = events.eventid UNION SELECT eventid FROM notifications WHERE eventid = events.eventid) AND eventtime &      lt; now() - interval '6 weeks'; </statement>
</VacuumdConfiguration>

Any help is appreciated.

Thank you.

Mario