We cannot join more than two sources using a single joiner. To join three sources, we need to have two joiner transformations.
Let’s say, we want to join three tables – Employees, Departments and Locations – using Joiner. We will need two joiners. Joiner-1 will join, Employees and Departments and Joiner-2 will join, the output from the Joiner-1 and Locations table.
Here are the steps.
- Bring three sources into the mapping designer.
- Create the Joiner -1 to join Employees and Departments using Department_ID.
- Create the next joiner, Joiner-2. Take the Output from Joiner-1 and ports from Locations Table and bring them to Joiner-2. Join these two data sources using Location_ID.
- The last step is to send the required ports from the Joiner-2 to the target or via an expression transformation to the target table.