In Vertica, tables are logical representations of the data. Vertica stores the actual data in projections. When data is loaded into a Vertica table, Vertica creates or updates a column-store projection. Vertica also compresses and/or encodes projection data, optimizing data access and storage.
If you experience performance issues, your best first step is to run Database Designer with sample queries and sample data. Database Designer creates projections that are optimized for those queries and data.
Learn more here: https://my.vertica.com/blog/query-optim ... ojections/