Joiner transformation is used to join two heterogeneous sources. You can join data from the same source type as well. The minimum criteria to join the data are matching columns in both the sources. A mapping indicating the Joiner transformation is shown in the following screenshot:

A Joiner transformation has two pipelines; one is called master and the other is called detail. One source is called the master source and the other is called detail. We do not have left or right joins like we have in the SQL database.

To use a Joiner transformation, drag all the required columns from two sources into the Joiner transformation and define the join condition and join type in the properties.