The Application or API Rule is the interface between the process engine and the application, including any parameters to be passed.
Based on their usage these are categorized into three types.
· Execution Rule: These are Business Logic executed as Task by an Activity.
· Decision Rule: This rule returns Boolean value “True/False”, used in decision making during split/branching of transition.
· Selection Rule: This rule fetches some value, useful to get value dynamically from a table or other source.
For example, select v_created_by from fct_expenses where id=101