When a scenario has been approved you Post it to the current forecast.
There are two post methods which have an impact on how assignments are posted. Labor and financial assignments behave identically.
Post Combine replaces current assignment values with scenario values (0 in scenario to remove current forecast demand)
Post Add creates new assignments for all scenario assignments; no impact on current forecast assignments
Both methods replace ALL project fields with scenario values with the exception of system fields like AID.
We have an initial state with two projects with the following assignment values.
This scenario moves demand from a 1/1/2021 start to a 6/1/2021 start. The scenario assignment 7479 has the original assignment 7467.
With this set of scenario values (there are 0 values in periods 1- 4/2021),
The result after Post Combine is:
With this set of scenario values,
The result after Post Add is:
Notice the ORIGINAL AID in row 3, 5514, matches the AID in row 2. But the post has created a new assignment in row 1 which got the AID 7482 after the Save.
NOTE: This is a risky method if there are any assignments in the scenario matching current forecast assignments (i.e. assignments with an ORIGINAL AID value). After post, these are potentially double counting demand.
A better use of Post Add is if all assignments in the scenario are incremental to the current forecast.
New assignments can be created in both the scenario project and the current forecast project AFTER the scenario was created with Include Assignments checked.
This means the original project(s) can have assignments not in the scenario and the scenario project(s) can have assignments not in the original project.
Row 1 is a new assignment in the original project. Row 4 is a new assignment in the scenario project.
Row 3 is the scenario assignment created from original assignment on Row 2.
The original project assignments now include the two that were the current project plus the new assignment from the scenario.
The assignment that had a matching scenario assignment (Row 2, AID 7467) now has scenario assignment (Row 5, AID 7479) values.
The assignment on the original project created after the scenario was created (Row 1, AID 7588) is unaffected by the Post operation.
The new scenario assignment (Row 4, AID 7589) is copied to the original project (Row 3, AID empty until saved).