Active and Passive Transformations

Active Transformations
Any transformation which changes the number of rows passing through it is called active transformations. If the number of input rows is not equal to output rows, then it is called active.

Source Qualifier
Joiner
Normalizer
Union
Filters
Routers
Sort
Rank
Aggregator
Transaction Control
Update Strategy

Passive Transformation
Any transformation which does not change the number of records passing through it is called passive transformation. If the number of input records = number of output records then it is passive.

Expression
Lookups
Stored Procedure
External Stored Procedure

Special Cases : -
Mapplet can be Active or Passive based on the transformations inside the mapplet. If it has any Active transformation, then it is active otherwise it is passive.

Interview Questions :-
1) Is a Mapplet Active or Passive - based on the transformations inside the mapplet
2) Why is a sorter active transformation - beacuse it has "Sort Distinct" property which will return distinct values.