The Rank transformation
The Rank transformation is used to get a specific number of records from the top or bottom. Consider that you need to take the top five salaried employees from the EMPLOYEE
table. You can use the Rank transformation and define the property. A sample mapping indicating the Rank transformation is shown in the following screenshot:
![](https://static.packt-cdn.com/products/9781782176480/graphics/6480EN_07_25.jpg)
When you create a Rank transformation, a default RANKINDEX
output port comes with the transformation. It is not mandatory to use the RANKINDEX
port. We have connected the RANKINDEX
port to the target as we wish to give the rank of EMPLOYEES
based on their SALARY
.
When you use a Rank transformation, you need to define the port on which you wish to rank the data. As shown in the following screenshot, we have ranked the data based on SALARY
:
![](https://static.packt-cdn.com/products/9781782176480/graphics/6480EN_07_26.jpg)
You cannot rank the data on multiple ports. Also, you need to define either the Top or Bottom option and the number of records you wish to rank in the Properties tab. In our case, we have selected Top and 5...