Using the Compare feature of Microsoft Project.

One of the most useful features of MS Project I have found is the Compare feature.  Compare is as you can guess, it compares one .mpp file with another.  This is most useful when comparing two versions of the same file. The Compare feature is in Project 2010 and 2013.  Project 2007 does not have a Compare feature.  Project 2003 has a Compare, but it was removed in 2007.  I have learned recently that there are situations where the Compare feature does not work in 2013.  The fix seems to be to ensure that the Microsoft Patches are applied.




When using Compare it is a good idea to not try to compare too many columns.  The more columns being compared, the more differences will occur.  The more differences there are, the more difficult it is to identify what has happened to the file.  One can't see the forest for the trees.  In my job, I receive monthly updates to the files that I review.  The first question is, what has changed?  The type of changes my management are most interested in are changes to the % Complete, Start Date, Finish Date and Duration columns.  Therefore, I have setup a table that includes these columns.  That way, I keep the changes at a manageable level.  Building this table will make using the Compare feature easier and faster.  Using the Organizer to store the table in your Global.Mpt file will allow use of the table in any file that you want to compare. 

So the process is to Open the two files that you want to compare, apply the table that you have built and then run the Compare. 

To use the Compare feature in 2010; click on the Compare Projects Icon in the Project Tab on the Ribbon:

















To use the Compare feature in Project 2013, Click on the Compare Projects icon in the Report tab on the Ribbon. 

Next, Project will present a window and ask you to confirm that you want to compare the file that is current (the file that was is displayed) to the other file that is open.  The first file is called the Current and the other file is labeled the Previous.  The only use of this is so that the two values for each column are labeled properly.  If you want the comparison reversed, cancel the window and make the other file active.  Then select the table you want to use for the task comparison and the table for the Resource comparison.  You can select "None" as an option for either comparison.   When the Compare Projects is finished, you will see the Comparison Report.  Project uses Custom columns for the additional columns needed, but since it creates a separate file for the Comparison Report this should not be an issue, The two original files are not changed. 

This image is from Project 2013, but the Report from 2010 is the very much the same.  Select "All Differences" from the top drop down list (default is All Items) and you will have a list of the tasks that are different between the two files.  My preference is to use the "All differences" option, but you can make your own choice.  The left most column in the report is an Icon column that tells you when a task occurs only in one of the two files or the task name has changed.  The Comparison Report is a Project file that can be saved like any Project file.  This allows the data in the Comparison file to be exported to Excel if desired for additional analysis.  I have used the export (or copy & paste) to Excel many times and Excel allows me to filter the data and record the counts of tasks where the Start Date has changed or the Duration has changed for example.  I have used this process to develop a monthly report of the number of task changes in the updated file.  It is useful to know how many tasks have changed in the % Complete column or how many tasks were added.

In summary, I have found the Compare function to be very useful in my job.