Thank for the tip! But...

I was just wondering how to do it DB-agnostic. Getting columns is a bit tricky with *my/PG/sqlite* environment due to their differences. I suppose Page cannot have columns as **predefined** array because some plugins **add** custom columns to Page model. Fixed array would prevent updating custom columns' values.

Meanwhile I moved the unsetter to Model, @NicNLD this can be discussed as another issue.