Dimensions are attributes that describe a given row of data, and measures aggregate dimensions. In Omni’s field picker, dimensions are listed in black while measures are listed in green.
If you’re selecting a field expecting it to be an aggregate, but instead you’re getting a list of possible values, you’ve probably selected a dimension, not a measure. Omni offers a quick way to create new measures — just right-click the field and select one of the quick aggregate options. Check out this post for more.
For example, if you’re looking at Orders data, each row represents one order, and each order will have a value for the dimension called sale_price. If you select sale_price from the field picker, you’ll get a list of all possible sale_price values rather than a sum (or other aggregate) of sale_price values. You can use Omni to quickly create a Sum version of this field, e.g. total_sale_price, that will aggregate sale_price across all selected rows.
