Two limits keep the history from growing without end. Both are set in the Configuration, and the Retention tab of Resource Versions (/admin/resource-versioning/retention) shows them, with how many versions are kept, for how many records, and the oldest.
Versions kept per record
Versions kept per record (50 by default) applies every time a version is recorded: when the record now has more versions than that, its oldest are deleted. 0 keeps every version.
Since the limit is per record, a record edited every day keeps its 50 newest states, while one edited now and then keeps its whole history.
Retention period
Retention period (days) (0 by default: keep forever) is how old a version may get before the prune deletes it. The prune deletes every version recorded longer ago than that, 1,000 at a time, whatever its record, kind or change, deletions and baselines included.
The retention period applies only when the prune runs. Omeka Classic has no scheduler, so nothing runs it on its own.
Pruning
- Set a Retention period (days) in the settings and save them.
- As a super user, open the Retention tab of Resource Versions. It says how many versions are older than the period.
- Click Prune old versions and confirm.
The prune runs in the background. Recent prunes on the same tab shows it, then how many versions it deleted. Only one prune runs at a time.
Pausing recording
Two settings write fewer versions without deleting any:
- Record versions off stops every new version; the history can still be browsed, compared and restored.
- Record bulk operations off skips the saves of batch edits and background jobs (CSV Import, Batch Edit All, scripts). Use it during a large import, then turn it back on.
A change made while recording is paused has no version, and cannot be undone with the plugin.