Lookup Transformation

Explain about Lookup Transformation

Lookup Transformation is a passive transformation which allows you to perform look up on relational table, flat files, synonyms and views
When a mapping contains a Lookup Transformation the integration service queries the look up data and compares it with look up input port values

The Lookup Transformation is created with the following ports

1. Input port (I)
2. Output port (O)
3. Lookup port (L)
4. Return port (R)

The Lookup Transformation supports horizontal  merging such as equi-join and non equi-join
Use Lookup Transformation to perform following tasks
       Get a related value 
       In updating Slowly Changing Dimension (SCD)


Connected and Unconnected Lookup will be discussed later