Rank Transformation in Informatica is similar to SQL RANK function, which is used to select the Top or bottom rank of data. In real-time, this transformation will be very helpful.
For example, you can use this Informatica rank transformation to select the top 10 regions with the highest and lowest sales Or bottom (underperforming) 20 products or regions etc.
For this Informatica rank transformation example, we are going to use the below show data
Configure Rank Transformation in Informatica
Before we start configuring the rank transformation in Informatica, First connect to Informatica repository service.
In order to connect with the Informatica Repository service, we have to provide the Informatica Admin Console Username and Password you specified while installing the Informatica Server. Next, click on Connect button.
Create Rank Transformation in Informatica Source Definition
Once you connected successfully, Please navigate to Source Analyzer and define your Sources. In this example, we are using [Employ] table from SQL Server database as our source definitions. Please refer Database Source in Informatica to understand the steps involved in creating source definition
Create an Informatica Rank Transformation Target Definition
Please navigate to Target Designer and define the Target. In this example, we are using the already created SQL table (Rank Transformation) as our target definition. Please refer Create Informatica Target table using Source Definition to understand creating a target definition
Creating Rank Transformation in Informatica Mapping
In order to create a new mapping for rank transformation in informatica, Please navigate to Mappings menu in Menu Bar and select the Create.. option. This will open the Mapping Name window as shown below. Here, you have to write a unique name for this mapping (m_Rank_Transformation) and click OK button.
Next, Drag and drop the [Employ] source definition from Sources folder to the mapping designer. Once you drag the source, the PowerCenter designer will automatically create the default transformation called source qualifier.
Create Rank Transformation in Informatica
In order to create Rank transformation in Informatica, Please navigate to Transformation menu and select the Create.. option as we shown below.
Once you click on the Create.. option, Create Transformation window will be opened as shown below. Please select the Rank Transformation from the drop-down list and specify the unique name (rnk_Income) for this transformation and click on Create button
Once you click on the Create button, the Informatica rank transformation will be added to the mapping designer.
To rank the data, rank Transformation requires some data. So, we have to connect the Source definition with the transformation by dragging the required fields.
From the above screenshot, you can observe the new item called RANKINDEX and this is default port created by the rank transformation. This output port will hold the ranking number so, we have to assign this output port to target table rank column.
Double click on the Informatica Rank transformation to provide the ranking factor (based on which column you want to rank). From the below screenshot you can see the list of available properties in the Transformation tab:
- Select Transformation: By default, it will select the transformation you clicked on.
- Rename: This button will help you to rename the rank transformation to a more meaningful name.
- Make Reusable: If you check mark this option then, this transformation will become reusable transformation.
- Description: Please provide a valid description.
Below screenshot will show you the list of available options in the Informatica Rank Transformation Ports tab:
- Port Name: List of available column names. By clicking the New column button you can add new columns and by clicking the scissors button you can delete the unwanted columns.
- I: Columns that are check-marked under this section are the rank transformation Input columns.
- O: Columns that are check-marked under this section are the rank transformation Output columns. If you unchecked any column then, that column will not be available to load in a target table.
- R: Please checkmark the Column that you want to use as ranking factor (based on which column you want to rank). For example, If you want to rank the data by yearly Income then you have to checkmark it as we shown below.
Below screenshot show you the list of available options in the Informatica Rank Transformation Properties tab.
- Cache Directory: Integration service will store the Cache files in this location.
- Top/Bottom: This will provide two options for the user i.e, Top and Bottom. If you want to rank the data from top to bottom (Z to A) then use the Top option or, if rank the data from bottom to top (A to Z) then use Bottom option.
- Number of Ranks: Please enter the number of rows you want to rank for. By default, the value will be 1 and it means, the Informatica rank transformation will select only 1 record.
- Case Sensitive String Comparison: If you check mark this option then, While sorting the data transformation will perform Case Sensitive String Comparison
For this example, we want to rank every record present in Employ table based on their Yearly Income (in descending order) that’s why we selected Top/Bottom property value as Top as and the Number of Ranks property value as 20 (our maximum records are 14)
Once you finish configuring the properties, Click OK to close the transformation window.
Next, Drag and drop the target definition (Rank Transformation) from Targets folder to the mapping designer and connect the Transformation with the target definition. Please use the Autolink.. option to connect them.
Before we close the Mapping, Let us validate the mapping by going to Mapping Menu bar and selecting the Validate option.
Creating a Workflow for Rank Transformation in Informatica
Once we finish creating the Mapping we have to create the workflow for it. PowerCenter Workflow manager provides two approaches to create a workflow.
In this Informatica Rank Transformation example, we will create the Workflow manually. To create new Informatica Workflow, Please navigate to Workflows Menu and select the Create option. This will open Create Workflow window. Please provide the unique name (wf_Rank_Transformation) and leave the default settings.
Once we created the workflow, our next step is to create a session task for our Informatica Rank Transformation mapping.
Creating Informatica Rank Transformation Session
There are two types of sessions in Informatica:
For this Informatica Rank Transformation example we are going to create Non-reusable Session. Please navigate to Tasks Menu and select the Create option to open the Create Task window. Here you have to select the Session as Task type (default) and enter a unique name (S_Rank_Transformation) for the session.
Once you click on the Create button, a new window called Mappings will be opened. Here you have to select the mapping you want to associate with this session.
From the below screenshot you can observe that we are selecting the mapping (m_Rank_Transformation) that we created earlier (in Step 3).
Double click on the Session Task to configure it. Although we have to configure Sources, targets and some common properties, we are explaining only a few properties. We strictly recommend visiting Session in Informatica article to understand the remaining properties.
From the below screenshot you can observe that we assigned the $target variable to Connection Value, we changed the Target Load Type option from Bulk to Normal mode and check marked the Truncate target table option to truncate the existing data from the destination table.
From the below screenshot you can observe that the Rank Transformation in Informatica workflow is a valid one. Now, Let us start the Workflow by navigating to Workflows menu and selecting the Start Workflow option.
Once you select the Start Workflow option, Informatica PowerCenter Workflow monitor will be opened to monitor the workflow. From the below screenshot you can observe that our Informatica Rank Transformation workflow is executed without any errors.
Let us open the SQL Server Management Studio to check whether we successfully ranked the records using Yearly Income using the Informatica Rank Transformation or not.
We can achieve the above output using the following SQL Query:
SELECT [FirstName] ,[LastName] ,[Education] ,[Occupation] ,[YearlyIncome] ,[Sales] ,RANK() OVER ( ORDER BY [YearlyIncome] DESC ) AS RANK FROM [Customers]
Let us change the Top/Bottom property to Bottom and refresh the mapping. It means Informatica rank transformation workflow will rank the Employ table based on the Yearly Income in Ascending order (0 as Rank 1, 1 as Rank 2 …. )