Aggregate Types

You can use the following aggregate types in expressions:
Sum (Sum)
Avg (Average)
Min (Minimum)
Max (Maximum)
Count (Count)
StDev (Statistical standard deviation)
Var (Statistical variance)
Create an aggregate expression by using one of the functions that is listed above. For example, use Sum(Price) to create a summary of figures in a column named “Price.” There is no group-by functionality, therefore, all rows display the same value in the column. If a table has no rows, the aggregate functions return a null reference.