Expression Transformation

Explain about Expression Transformation

Expression Transformation
This is a connected and passive transformation. It allows you to calculate the expressions for each record. It is used to perform non aggregate calculations. An Expression transformation is used for calculations, string concatenations, converting string to numbers and also check conditional statements.
It allows you to add new ports.
An expression transformation supports to write expression either in variable ports or only in output ports
Use an expression transformation to derive the new attributes to change the inconsistent data into consistent format
An expression transformation is created with following types of ports

1. Input port (I)
2. Output port (O)
3. Variable port (V)

For an exercise on this transformation check this   http://prashanthobiee.blogspot.in/2012/12/exercise-to-implement-filter-rank-and.html