Add attribute rule ability to call database functions

AndrewRudin1

Add a new arcade function to the library that allows the code to call a database function. The value returned by the function will be populated into the field. This could be very similar to the NextSequenceValue function, but instead of providing the sequence name, the user would provide the database function name.

For my organization, this would allow us to build attribute rules that could call other Oracle databases (like our permitting system) via database links. For example if a GIS user is entering a new subdivision record, they would enter the permit number in one column. This new feature would allow us to call a database function with that permit number, retrieve information about the permit from the other database via a database link, and then auto-populate that information on the GIS record in other columns. 

AndrewRudin1

@Bud Maybe database triggers would work if the data is branch versioned since that eliminates the complication of delta tables being involved that the triggers aren't aware of.  We are still getting familiar with how the branch versioning works so maybe we'll rediscover some tricks that weren't applicable with traditional versioning and the delta tables

However, the better thing would be for Esri to allow calling a function.  That way our RDBMS savvy developers can build the functions, and then allow our GIS analysts to leverage them in attribute rules on the feature classes they maintain.

The nice thing about attribute rules is they live with the feature class definition, so no matter which Esri method you use to edit the data (Pro, Enterprise feature service, Geoprocessing tool), the same attribute logic is applied and esri handled, and the management is exposed on the ESRI GUI side for GIS analysts.  We are already having to implement attribute rules that come with newer Esri data management solutions, so it would be better to have all the custom data entry logic in one place, rather than having some in attribute rules and some in custom database triggers, and then you have to wonder which fires first.

Esri already allows calling a sequence from Arcade with the NextSequenceValue  function.  This expects that the user/dba has setup the sequence and granted the appropriate privileges for it to be used.  If they are okay with that then I don't see harm in expanding to also allow referencing a database function and assume that the DBA/Analyst will manage the function and privileges.  Esri may have to stipulate that the function only return one value, but that should cover most situations.