Method: Helper method to compute meta cache key. Different from WP Meta cache key in that meta data cached using this key also contains meta_id column.

Method: Generate cache key from id and group.

Method: Prime caches for raw meta data. This includes meta_id column as well, which is not included by default in WP meta data.

Method: Merge changes with data and clear.

Method: Prefix for action and filter hooks on data.

Method: Gets a prop for a getter method.

Method: Sets a date prop whilst handling formatting and datetime objects.

Method: When invalid data is found, throw an exception unless reading from the DB.

Method: Set a collection of props in one go, collect any errors, and return the result.