When activities are entered into a schedule, they appear in a numerically ascending order by activity ID. What happens if the project has evolved, and additional activities have to be inserted into the schedule? Change throughout a project life-cycle is inevitable and can create schedulers’ problems if new activities are entered and the activity ID needs to change. Let’s take a closer look.
In Figure 1, we have our ‘Pipe Repair-1’ project schedule which has the ID prefix S and the increment 10. We need to insert two activities after ‘Install Piping’ S1060.
Figure 1
In Figure 2 below, by entering the ‘Projects’ tab, we select ‘Defaults’ in the section at the bottom of the screen. The Activity ID Prefix is already S. By checking the ‘Increment Activity ID based on selected activity’ box we can be sure when we enter our new activities the ID Prefix remains the same (‘S’). In the Increment Box, we enter 2, this represents the two activities we are inserting into our schedule.
Figure 2
Next by highlighting S1060 ‘Install Piping’ and selecting ‘Edit’ and ‘+ Add’, twice. We type in the activity names of ‘Install Fittings’ and ‘Install Couplings’ and our two new activities are inserted into our schedule between S1060 and S1070, as displayed in Figure 3.
Figure 3
Although our two new activities have been inserted, they are not ascending in increments of 10 like the rest of our schedule. We also need to increase the increment between ‘Install Piping’ and ‘Install Couplings’ in preparation, in case we have to insert any more activities between them.
By highlighting all of our activities, we select ‘Edit’ and scroll down to select ‘Renumber Activity IDs’, as in Figure 4.
Figure 4
In the ‘Renumber Activity IDs’ box, as in Figure 5, we check the ‘Auto-number’. In ‘Prefix’ we add ‘CW’. This prefix is more appropriate for our schedule than ‘S’ as it means Construction Work.
We make sure that the ‘Suffix’ is 1000 and the ‘Increment Value’ is 10 which is the same as our schedule. We want to have a baseline that corresponds with this schedule so we check the ‘Renumber selected activities in baseline’ box.
Figure 5
Our activity IDs are renumbered as shown, in Figure 6 when we select ‘OK’.
Figure 6
Primavera P6 Professional will offer a duplicate activity ID warning if the same prefix is used when renumbering activities, which is why we changed our Prefix from ‘S’ to something more appropriate to our schedule ‘CW’. Our renumbering is correct with ascending increments of 10 for each activity. To capture our two new activities ‘Install Piping’ and ‘Install Couplings’ on our baseline we have to create a new baseline. We must copy the current updated project as a new baseline.
We elected to renumber the selected activities in the baseline, therefore we should review our baseline.
Updating the Baseline
We remove the assignments for our respective Pipe Repair -1 (Pipe Repair & Improve) baseline. By selecting ‘Maintain Baselines’ we restore our baseline. This unlinks the baseline and places it in the EPS. As shown in Figure 7.
Figure 7
Below in Figure 8, we have our baseline ‘Pipe Repair & Improve-B2’
Figure 8
Our baseline file has the same ascending numbering scheme.
Summary
Renumbering activity IDs is not something schedulers recommend or is it considered best practice. You should leave room in your activity numbering scheme to accommodate the inevitable changes in your schedule.
When you insert or delete activities in Primavera P6 Professional, you should update your baseline as these changes are not automatically captured.
Remember you must change the prefix when renumbering your activity IDs, otherwise, you will receive a duplicate activity ID warning.