Split Primavera P6 Schedule into 2 Schedules - Problem and solution

I have received a question from one of my trainees as follow “I have schedule of work around 50,000 activities and the schedule contains the scope of work of two contractors. Now one contractor will not be working under us and i need to maintain the dependencies between the 2 scope of works and in the same time remove other contractor activities from my schedule. Or maybe split the schedule into 2 activities”

My answer to this challenging question was as follow:

1- Following is a screenshot of the test schedule where there is project A (the one you want to delete) and project B where there are relationships from Project A

2- I will export excel spread sheet (Activities and Activities Relationships) :

3- Select the following columns:

A: Activities:

B: Activities Relationships:

4: Now we want to find out which activities in Project A that have relationships with project B to keep it and delete other activities Following screenshot showing the technique used to find this using excel also the excel sheet attached:

You need to identify the project A and project B using the activity ID; so we need to know if there is a Successor in project A that has Project B.

A: Column H Formula will find if the Successor column has the word “Project B”: =ISNUMBER(SEARCH(“ProjectB”,B3))

B: Column I Formula will find if the Activity belongs to Project A: =ISNUMBER(SEARCH(“ProjectA”,A3))

C: Column J will find if the both columns (H & I) are true to tell us this is required activity: =IF(AND(H3=TRUE,I3=TRUE),”Required”,”Not Required”)

5: Now we will go to the activity sheet to make Vlockup to find the required and not required activities in Project A. Not required activities will be deleted by add letter “d” as per below screenshot and required activities will add a constrain must finish by = early finish date.

6: Now clean your sheet by deleting the relationships sheet and paste value your data in activities sheet and import to your schedule and here is the result:

Only the activities that affect project B remains with constrain to finish by its planned date: