Audit Trail Options

Options to specify how long the audit trail is kept and how much is "current" vs compressed are accessed through the Audit Trail Options dialog.  To get to this, go to View / Audit Trail, and click the "Audit Options" button.

Compress older entries after ... days -- It's recommended to leave these settings at the defaults for most installations.  In extreme cases of a very busy system it might make sense to keep less of the audit trail current/uncompressed, since compressing the audit trail saves about 90% of the space.  The recommended defaults are to compress after 30 days, keeping 15 days current (so after the first 30 days, every 15 days it will compress the oldest 15 days, keeping 15 days uncompressed for faster access.

Compress in blocks of... bytes -- This can affect the effectiveness of compression in extreme cases.  The smaller the block size, the less efficient it can compress, but anything above 25,000 won't make a lot of difference.

Permanently delete entries older than ... days -- For PCI compliance (for credit cards), this must be at least 366.  If your business is not very busy, you might want to increase this since the database can handle more entries.  In extreme cases, this may need to be made much shorter -- however, that means you must manually archive older entries to meet PCI compliance standards.

Manual compression -- This function can be used to manually compress entries, e.g. ahead of their scheduled time.  This could be handy if you have a large amount of changes on a single day for some reason and want to reduce the database size.

Show Stats -- This simply shows how much memory the audit trail is using, which can be useful in deciding if changes need to be made in the settings.  If the Current entries usage exceeds 1000 kB, then you may want to compress more often (keep fewer days current).  If the Compressed usage exceeds 50,000 kB, then it's probably becoming an excessive burden on the database and you may need to have it permanently delete entries sooner.