When you save or publish a plan to Project Server, different changes are made to the Project Server database. Understanding the flow of data will be helpful in understanding how Project Server operates.

If you open the Project Server database in SQL Server Enterprise Manager, you will see that there are tables that begin with MSP_, some that begin with MSP_WEB, some that begin with MSP_VIEWS, and some that begin with MSP_CUBE.

Each set of tables is associated with part of the Project Server EPM solution. The tables that begin with MSP_ are those tables that store information from Project Professional. The tables that begin with MSP_WEB and MSP_VIEWS are those that deal with Project Web Access. As you might guess, the MSP_CUBE tables deal with the building of OLAP cubes.

What are the implications of these relationships? Well, the MSP_ tables hold the same data from Project Professional as would be contained in an MPP file saved to your local hard drive. In other words, when you are using Project Pro as a stand-alone tool, not connected to Project Server, you create a file such as "Project.mpp" when you save your project plan to your local computer.

When you are connected to Project Server and save the project plan, the same information that is stored in the "Project.mpp" file will be stored in the Project Server database within the MSP_ tables.

What is important to note here is that this is what happens when you SAVE a project when using Project Pro and you are connected to Project Server. Saving the project plan writes the project information to the set of tables that begin with MSP_. The other tables are not affected by saving the project plan.

The tables that begin with MSP_WEB and MSP_VIEWS receive their data when a project plan is PUBLISHED. What happens is that "saving" puts the data into the MSP_ tables and then "publishing" your project draws data out of the MSP_ tables and writes the information to the MSP_WEB and MSP_VIEWS tables. It is only after the MSP_WEB and MSP_VIEWS tables receive their data that the new information is available to be viewed in Project Web Access.