Define Aggregate Dialog Box

You use the Define Aggregate dialog box to aggregate the values of a specified field into a single field, according to the specified operation.

You display the Define Aggregate dialog box by selecting an Aggregate operator icon on the Design board and clicking the browse button next to the Configuration field in the Configure Element task panel, or by right-clicking the Aggregate operator icon on the Design board and choosing Define Operator from the context menu.

The Define Aggregate dialog box contains the following items:

Item	Description
Add Row	Adds another row to the list. You can then define how to aggregate the data.
Delete Row	Removes the highlighted row from the list.
Move Up	Moves the highlighted item one place up in the list, giving it higher priority.
Move Down	Moves the highlighted item one place down in the list, giving it lower priority.
Field	The field whose values you want to aggregate. In the dropdown list, you can select a field from the data source connected to the operator, or you can select Define expression to define a field using the Dynamic Expression Editor dialog box.
Operation	The aggregate operation to perform on the field values. You can choose from the following operations: Average: Returns the average (arithmetic mean) of the field values. Available only for fields of type Number. Count: Returns the total number of field values that are not blank. Max: Returns the greatest field value. Min: Returns the lowest field value. Median: Returns the median field value. The median is the number in the middle of a set of numbers. Sum: Returns the sum of all field values. Available only for fields of type Number. Std dev: Estimates the standard deviation based on the field values. The standard deviation is a measure of how widely values are dispersed from the average value (the mean). Available only for fields of type Number. Variance: Estimates the variance based on the field values. The variance is a measure of the squared distance of the possible field values from the expected value (the mean). Available only for fields of type Number. Group by: Groups the field values by the specified field name, in ascending or descending order.
Condition	The criteria that must be met for the aggregate operation to be performed. You can enter a condition, or click the fx button to define a condition using the Dynamic Expression Editor dialog box. This option is not relevant for the Group by operation.
Direction	The direction in which to group the data. For example, you can group text, numbers, or data in ascending (Up) order (A to Z, zero to 9, or earliest to latest date). Or, you can group values in descending (Down) order (Z to A, 9 to zero, or latest to earliest date). This option is only relevant for the Group by operation.
Field Name	The name of the new data field to which to assign the result of the aggregate operation.
Description area	Displays a description of the selected aggregate definition, in plain-language sentence format. For example, `Return Count of =@CITY as City, group by =@BANK_CTRY as Country Ascending`.