Aggregation is the process of examining quantitative values or measurements at higher and more summary levels of data. Tableau automatically aggregates data when you put a measure on a shelf, generally by adding it. When a field is placed on a shelf, the function always displays in front of the field’s name, making it easy to discern the aggregate applied to it. Sales, for example, becomes SUM (Sales). Tableau can only aggregate measures for relational data sources. Only aggregated data is contained in multidimensional data sources. Tableau only supports multidimensional data sources on Windows. Disaggregating your data, according to Tableau, allows you to see every row of the data source, which is important for examining measurements that you may wish to utilize in the view both independently and dependently. For example, suppose you’re looking at the results of a product satisfaction survey and one of the axes is the age of the participants. You may use the Age variable to discover the average age of participants, or you can use it to disaggregate the data to see which age groups were the happiest with the product.