The transformation language includes the following aggregate functions:

If you use a port in an expression in the Aggregator transformation but you do not use the port within an aggregate function, the Data Integration Service uses the last row in the port to process the expression.

For example, you create an Aggregator transformation that contains the ports

COMMISSIONS

and

SALARY

. The port

SALARY

is a group-by port.

You might use the following expression in an output port:

SUM(COMMISSIONS)

The Data Integration Service processes the Aggregator function and returns the sum of the values in the port

COMMISSIONS

in the output port.

You might modify the expression to the following expression:

SUM(COMMISSIONS) + COMMISSIONS

To process the expression, the Data Integration Service returns the sum of the values in the port

COMMISSIONS

and adds the value of the last row in the port

COMMISSIONS

to the return value in the output port.

For a different output port, you might use the following expression:

SUM(COMMISSIONS) + SALARY

To process the expression, the Data Integration Service returns the sum of the values in the port

COMMISSIONS

and adds the value in the last row of the port

SALARY

to the return value in the output port. Note that the values in each row of the port

SALARY

are the same because the

SALARY

port is a group-by port.