Each night at midnight the loader sends a SQL command to the SQL server to purge old log information. That command is as follows :
DELETE FROM LogTable WHERE LogTime < 'some date';
'some date' is formatted like this: yyyy-MM-dd HH:mm:ss
If your database is very large then this command may not be able to finish each night because your database typically has transnational roll back configured. This makes a copy of the data prior to purging which may fail if you do not have enough space. Each DB system sets this up slightly different so please refer to your DB vendor for how to disable transaction logging for the webNetwork logging database. Transaction logging is a great feature for many types of data, but not needed for the relay log data.
Another way to purge the DB by hand is to add the LIMIT command to limit the number of records being purged. This is easier than trying to come up with a SQL statement that gives a smaller subset of data.
DELETE FROM LogTable WHERE LogTime < 'some date' LIMIT 10000;
This would limit the delete to 10,000 entries. If you ran it multiple times it would delete a batch of 10,000 records each time thus getting around the problem with the transaction roll back settings.
As of 6.2.0.51 and higher, we have limited the amount of data that gets logged in the relay request logging. We filter out things like .gif, .jpg, .png, .css, .js. This helps to keep the database smaller.
The webNetwork Audit DB does not have an auto purge, thus you will want to periodically purge the data using a command such as : delete FROM auditdata where datetime < '2015-01-01 00:00:00' LIMIT 100000; This would purge data older than 2015-01-01 and do it in a batch of 100,000 records at a time.