Attribute table Fields that automatically update

Idea created by kmacleod on Feb 16, 2011
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    Why is there no Check Box that makes a field automatically update its values? For example, I frequently deal with tables that have an Area field. It will be in Acres for example. If you're doing UTM, the field will have been calculated using a conversion from square meters to acres. As of now...you have to continuously and manually re-calculate the Field. It's easy to forget to do this if you just change one record's geometry. 

    Am  I missing something, or is this not possible? If not...ESRI can you add a Check Box that automatically updates values of Fields when a record changes?  When you are in the Field Calculator or Calculate Geometry dialogue, it can remember WHAT you were calculating so that it re-calculates the field the exact same way. For example if you enter an expression in Field Calculator, ArcGIS will remember this expression and re-calculate it automatically when changes occur to the geometry. Of course, this could also apply to other fields and types of changes.

    Also, why doesn't a Field store the way it was calculated? There should be an option to remember the Expression used to calculate a field, or the method used to calculate it if Calculate Geometry was used. (Or is this stored somewhere?)

    If these features are present and I missed them and someone can post where they are in comments, thank you in advance! :)