11. What is a cached lookup transformation and uncached lookup transformation?

Cached lookup transformation: The Integration Service builds a cache in memory when it processes the first row of data in a cached Lookup transformation. The Integration Service stores condition values in the index cache and output values in the data cache. The Integration Service queries the cache for each row that enters the transformation.

Uncached lookup transformation: For each row that enters the lookup transformation, the Integration Service queries the lookup source and returns a value. The integration service does not build a cache.