Join Stage

1)The  ‘Join’ stage  is a processing stage  that performs a  join operation on  two or more  input data sets and then provides output in the form of one resultant data set. 

2)The following four types of joins can be performed: 
•  Inner join 
•  Left outer join 
•  Right outer join 
•  Full outer join 

3)The  join stage supports 2 or more sorted input links and 1 output link

4)The  join stage editor allows you  to specify  the keys on which  join  is performed. More  than one key can be specified. Specified keys should have same name on all links. 

5)No fail/reject option for missed matches 

6)Link ordering is very important while using left or right outer join and also the input data on all links to join stage should be sorted.

 Capturing unmatched records from a Join:
a)The Join stage does not provide reject handling for unmatched records.If unmatched rows must be captured,an OUTER join operation must be performed,so that when a match does not occur, the Join stage inserts Null value into the unmatched non-key columns provided non-key column is defined as nullable on the Join input links.

b)After Join  Stage Use Transformer to filter Null records with the help of IsNull Built function