I would like to build a database that has records in flux and records that are locked. The records that are in flux–the current period, whether monthly, quarterly, or annually, would be separated from locked records by a closing date (or other number/field I suppose) that determines the cutoff or closing whereby that prior records are deemed complete and not subject to change. So I am imagining a field type that is “Closing number” that could be a date or some other ordinal type that could be included in a table, and then an option under the “+” tab at the upper right of the menu, which offer “Closing date”. If you selected “Closing date” from the menu, you could choose a particular date or number, and all prior records would be locked. You could reverse this, but only after getting a warning message and perhaps entering your password.
This same method could be used to protect sensitive information as well: You could have a field type: “Protection” and designate user levels to access/view/modify the information.