Math operations on tables
When working with data in Power Apps, there are many reasons to perform math operations across your data. This math can be counting functions or aggregate functions. Both support tables of data. Not covered in this module are additional math functions and operators for non-table data. For a complete list of all functions, see Formula reference for Power Apps.
Counting functions
Counting functions are used to compute the number of records in a table of data based on criteria. They’re often used to provide visual indicators back to the user.
For example, you could use CountIf(TasksTable, Complete = "No") to count the number of records in the TasksTable where the column Complete equals No. Then based on the total, you could conditionally format the Color property of a label or change the Visible property of an icon. These types of visual indicators improve the user experience.
Power Apps includes the following counting functions:
Count counts the number of records that contain a number in a single-column table.
CountA counts the number of records that aren't blank in a single-column table. This function includes empty text ("") in the count.
CountIf counts the number of records in a table that are true for a logical formula. The formula can reference columns of the table.
CountRows counts the number of records in a table.
Count and CountA only support single-column tables, and that is the only argument they accept.
CountIf accepts a table and then the logical formula to process. It then returns a count of all the records that match the logical formula.
CountRows accepts only a table as an argument and then returns a count of the number of rows in that table.
Aggregate functions
The aggregate functions are used to provide summary information from a table of data. Information like the average sales price or the standard deviation of scores. Think of it as simple reporting on your data that enables a better app experience.
For example, you could use Max(CustomerOrders, SalePrice) to find the maximum value stored in the SalePrice column of the CustomerOrders table. With this information, you could confirm that the price entered in a Form control didn’t exceed that price before letting the user submit the form.
Power Apps includes the following aggregate functions:
Average calculates the average, or arithmetic mean, of its arguments.
Max finds the maximum value.
Min finds the minimum value.
Sum calculates the sum of its arguments.
StdevP calculates the standard deviation of its arguments.
VarP calculates the variance of its arguments.
All of these functions support data being passed directly to them, such as: Average(9,10,8)
This formula would return the value 9, which is the average of the three input values.
Or by passing a table and expression to them such as: Average(OrdersTable, OrderAmount)
This formula would return the average of the OrderAmount column from the OrdersTable. In a later unit, you’ll learn how to split and combine data with functions.