The following example shows how you can use the Sequence transformation to generate primary keys.
You are gathering customer data and need to assign customer IDs to each customer. The CustomerData.csv flat file contains your source customer data. You create a mapping that includes the Sequence transformation to create customer IDs, using the following process:
Create a copy of the CustomerData.csv file to use as the target and then add the cust_id field to the file to hold the generated customer ID values. You name the file CustomerData_IDs.csv. The following image shows a sample of the file:
Create a connection that has access to the CustomerData.csv and CustomerData_IDs.csv files.
Create a mapping in the Mapping Designer and add a Source transformation to the mapping. You configure the transformation to use the CustomerData.csv file.
Add a Sequence transformation to the mapping.
To generate a simple sequence starting with 1, set the
Initial Value
to 1 and the
Increment By
value to 1. This configuration starts the sequence at 1 and increments the value by 1, for example, 1, 2, 3.
You leave the default values for the other properties. The following image shows this configuration:
Add a Target transformation to the mapping and configure the transformation to use the CustomerData_IDs.csv file that you created.
Connect the Source transformation to the Sequence transformation and the Sequence transformation to the Target transformation:
In the Target transformation, map the NEXTVAL output field to the cust_id field.
Save the mapping and create a
mapping
task in the
mapping
task wizard. The
Current Value
is 1 because the mapping hasn't been run yet and the
Initial Value
is 1.
After running the
mapping
task, view the
mapping
task details. The task details show the current value and the initial value of the sequence.
Open the CustomerData_IDs.csv file and note that the cust_id field is populated with a numeric sequence:
ASK INFAPreview
