Re: how to get drop down data from database in alfresco workflow
I am reluctant to populate list constraints in the data model from a database because if/when those records change, you will see constraint violations in your repository. However, if you want to do that, you can just write a custom list constraint class.
If the intent is that you want to have a dropdown that is populated from a database call, there are multiple ways to do that without requiring a custom list constraint.
For example, you could:
1. Write a custom form control and have the form control use an AJAX call to call an external (non-alfresco) service. The service will return the list of items for the dropdown. Where that service gets the list is up to you--it could be a database query.
2. Write a custom form control that makes an AJAX call to a web script. That web script can query the database or some other external service for the dropdown items.
Either of these is probably better than writing a custom list constraint that makes a database call.