Question

What are the types of lookup transformation?

Answer 1

There are four different types of lookup transformation:

• Relational or flat file lookup: It performs lookup on relational tables.
• Pipeline lookup: It performs lookup on application sources.
• Connected or unconnected lookup: While the connected lookup transformation receives data from source, performs lookup, and returns the result to the pipeline, the unconnected lookup happens when the source is not connected. It returns one column to the calling transformation.
• Cached or uncached lookup: Lookup transformation can be configured to cache lookup data, or we can directly query the lookup source every time a lookup is invoked.