Merge Join component is used when we want to merge the data coming from different source or data flow. Merge Join provide us the data as a combine source or single source after merging the data from different sources.
Point to be noted: For using Merge Join it’s mandatory to use Sort component.
Merge Join: Combine two sorted data flows into one using the FULL, LEFT, or INNER join. It’s recommended that during transformation of data flows sorting to be used at their sources.
Merge Join Editor: Here, we get the ability to specify the type of join we want for merging the data coming from Sort components. Under this editor we can either use Inner Join, Let Outer Join or Full Outer Join.
Under merge join component we get all the fields/attributes which are passed under Sort component from their respective data source.
Now, we need to map the fields coming from different sources and pass through Sort component. If the fields is not marked for Pass Through under Sort then the field won’t populate under Merge Join Editor and mapping would not be possible for that field.
Under Sort Editor we need to check the field under Pass Through column. If the field is unchecked then the field would not populated under Merge Join component editor.
Example: If the checkbox next to UniqueID is not checked under Pass Through, then it would not populate under Merge Join Component Input Column.
Also, we need to select one field on top of which sorting order would be done.
In my case I selected a field which contains unique data in the entire data flow fields.
We can also decide the Sorting Order for the fields as it should be in ascending or descending order.
Hope this explanation help you!