Informatica Common components lookup two connected and disconnected lookups

You can configure a connected Lookup transformation to receive input directly from the mapping pipeline, or you can configure an open Lookup transformation to receive input from the expression results of other transformations.

Connected Lookups	non-connected lookups
Receives input values directly from the pipeline.	The input value is received from the other converted: LKP expression result.
You can use either dynamic or static caches.	You can use a static cache.
The cache includes all lookup columns used in the mapping (that is, the lookup source columns that are included in the lookup criteria, and the lookup source columns that are linked to other transformations as output ports).	The cache includes all lookup/output ports and find/Return ports in the lookup condition.
Multiple columns can be returned from the same row, or inserted into the dynamic lookup cache.	Specifies a return port (R). Returns a column from each row.
If no items matching the lookup criteria are found, PowerCenter Server returns the default values for all output ports. If you configure dynamic cache, PowerCenter Server inserts rows into the cache or makes no changes.	If no items matching the lookup criteria are found, PowerCenter Server returns NULL.
If there are entries that match the lookup criteria, PowerCenter Server returns the results of all lookup/output port lookup criteria. If you configure dynamic caching, PowerCenter Server updates the rows in the cache, or does not make any changes to the rows.	If there are entries that match the lookup criteria, PowerCenter Server Returns the result of the lookup condition to the return port.
Pass multiple output values to other transformations. Link the Find/output port to other transformations.	Pass an output value to another conversion. The lookup/output/return port passes the value to the transform of the call: LKP expression.
User-defined default values are supported.	User-defined default values are not supported.

Connected Lookup transformations

• The Connected Lookup transformation receives input values directly from other transformations in the pipeline.

• For each input row, PowerCenter queries the lookup source or cache based on the lookup port and criteria in the transformation.

• If the conversion is not cached or the static cache is used, PowerCenter Server returns the value of the lookup query.

If the transformation uses dynamic caching, PowerCenter Server inserts the row into the cache when no rows are found in the cache. If the PowerCenter Server finds rows in the cache, the rows in the cache are updated or no changes are made. It marks the row as insert, UPDATE, or no change.

• PowerCenter Server passes the value returned from the query to the next transformation.

If the transformation uses dynamic caching, you can pass the row-to-filter or router-to-switch to filter the new rows to the destination.

Non-connected Lookup transformation

• A Lookup transformation that is not connected from another transformation, such as an update policy transformation, receives an input value from the LKP expression result.

• PowerCenter Server queries the lookup source or cache based on the lookup ports and conditions in the transformation.

• PowerCenter Server Returns a value to the return port of the lookup transformation.

• The Lookup transformation passes the return value to the: LKP expression.

Informatica Common components lookup two connected and disconnected lookups