The VertiPaq engine is an in-memory columnar database that sits behind Excel Power Pivot, SQL Server Analysis Services (SSAS) Tabular, and Power BI. When you load data into a data model, it is loaded, compressed, and stored in RAM using the VertiPaq engine. You may also see it referred to by its newer official name, the xVelocity engine, but it is still widely known by the code name used during its development, and this is how we will refer to it in this book.
Understanding how this database engine processes data when it is loaded into a data model, even at a basic level, is essential if you want to build efficient data models.
The VertiPaq engine is only relevant when you are importing data into a data model. If you are using DirectQuery to connect to your data, then the VertiPaq engine is not used.
With a traditional database, data is stored in...
