populating select field options from mysql table

mikefnasr

using the editor, when editing or creating new entry, i have a select type field with several option, how to populate these options dynamically from a mysql table?
i found a way to edit the html under the specific field to connect to db and get data, however would like to know how to do it the correct way, i assume i need to edit the js file under js/table.<tablename>.js

please let me know if anyone found a solution for this, and can provide a basic example.

DataTables is super helpful, i cannot imagine doing things related to data entry without it.

Thank you