Day7

 Design a mapping to find the sum of salaries of all employees and this sum should repeat for all the rows.
The output should look like as

employee_id, salary, salary_sum
10, 1000, 11000
20, 2000, 11000
30, 3000, 11000
40, 5000, 11000

Solution:

Step1: Connect the source qualifier to the expression transformation. In the expression transformation, create a dummy port and assign value 1 to it.

In the expression transformation, the ports will be

employee_id
salary
O_dummy=1

Step2: Pass the output of expression transformation to aggregator. Create a new port O_sum_salary and in the expression editor write SUM(salary). Do not specify group by on any port.

In the aggregator transformation, the ports will be

salary
O_dummy
O_sum_salary=SUM(salary)

Step3: Pass the output of expression transformation, aggregator transformation to joiner transformation and join on the DUMMY port. In the joiner transformation check the property sorted input, then only you can connect both expression and aggregator to joiner transformation.

Step4: Pass the output of joiner to the target table