In ArcGIS, what are the options for automatically computing a field in an enterprise geodatabase?
Any other options/ideas?
I appreciate you said ArcMap, but have you seen the attribute rules in ArcGIS Pro:
Introduction to attribute rules—ArcGIS Pro | Documentation
And in particular the calculate rules:
Calculation attribute rules—ArcGIS Pro | Documentation
Seems like a pretty comprehensive list...
for 5a: You could export the query layer as CSV or XLSX and use that in your report.
The method you use will probably depend on
For example, if you need to generate a monthly report in Excel, and that's the only place where you consume the field, it would probably be overkill to use SOE or even scheduled jobs and triggers. Just run a script or tool beforehand.
If you need the report daily, or if you need the field in other applications, it would be a good idea to use jobs or triggers.
If the data has to be current, then you should probably use queries or triggers. Which one could depend on performance: queries would give performance hits for consuming, triggers would give performance hits when editing. If the data doesn't have to be current, a scheduled job could suffice.
Server customization seems like overkill in any case. Maybe for really special cases where you can't achieve your goal with SQL, Python or Arcade, or where performance really matters.
Manually use the field calculator in ArcMap
For simple stuff like concatenating two fields, sure. For more complex stuff like getting related data or spatial relationships? Either write a small script or run it manually once, then save the Python command as script.
Manual data entry in attribute table in ArcMap
For things you don't expect to change and if you edit only few feature, sure. If other applications depend on you not making errors in the process, or if you know the values can change, or if you edit 10s or 100s of features in one go: no. Just finish editing and run CalculateField.