What is the use of unconnected lookup transformation in Informatica?
You can use an unconnected Lookup transformation to replace cryptic or numeric ID values in a table with meaningful names from a lookup table. For example, you need to load some sales order data from SAP transactional tables to a relational table in your data warehouse.
What is unconnected lookup in Informatica?
An unconnected Lookup transformation is a Lookup transformation that is not connected to other transformations in a mapping. A transformation in the mapping pipeline calls the Lookup transformation with a :LKP expression. The unconnected Lookup transformation returns one column to the calling transformation.
How do you call an unconnected lookup?
Calling an unconnected lookup from another transformation
- Use the following syntax for a :LKP expression:
- :LKP.
- The arguments are local input fields that match the Lookup transformation input fields used in the lookup condition.
Which of the following is unconnected transformation?
Some of the Major connected Informatica transformations are Aggregator, Router, Joiner, Normalizer, etc. Those transformations that are not connected to any other transformations are called Unconnected transformations.
What are the advantages of unconnected Lookup?
Reusability: An Unconnected Lookup Transformation is reusable within a mapping. Its performance is better than Connected Lookup transformation, because it returns only one output port.
Can we use dynamic cache in unconnected lookup?
Unconnected Lookup Does Not Support Dynamic Cache.
What are the advantages of unconnected lookup?
Why is unconnected lookup used?
The primary purpose of Unconnected lookup is to be called for the lookup value multiple time based on the need and it is not a direct link to the mapping flow It is, just like a variable defined in an Expression transformation.
How many types of transformations are there?
There are 3 Informatica transformations viz. External Procedure, Lookup, and Stored Procedure which can be unconnected in a valid mapping (A mapping which the Integration Service can execute).
What is difference between active and passive transformation in Informatica?
A transformation can be active or passive. An active transformation can change the number of rows that pass through the transformation. A passive transformation does not change the number of rows that pass through the transformation.
What is the difference between connected and UnConnected lookup in Informatica?
Connected lookup receives input values directly from mapping pipeline, whereas UnConnected lookup receives values from the lookup expression from another transformation. Connected lookup caches all lookup columns, whereas UnConnected lookup caches only the lookup output and lookup conditions.
How does the unconnected lookup transformation work in Informatica?
Connected lookup transformation receives input values directly from the pipeline. Unconnected lookup transformation receives input values from the result of a :LKP expression in another transformation. Connected lookup transformation can be configured as dynamic or static cache.
How to create an unconnected lookup in LKP?
Supply input values for an unconnected Lookup transformation from a :LKP expression in another transformation. The arguments are local input ports that match the Lookup transformation input ports used in the lookup condition. Use the following syntax for a :LKP expression: :LKP.lookup_transformation_name ( argument, argument.)
Can a unconnected lookup transformation be used as a static cache?
Unconnected lookup transformation can be configured only as static cache. Connected lookup transformation can return multiple columns from the same row or insert into the dynamic lookup cache. Unconnected lookup transformation can return one column from each row.
What happens if there is no match for the lookup transformation?
If there is no match for the lookup condition, connected lookup transformation returns default value for all output ports. If you configure dynamic caching, the Integration Service inserts rows into the cache or leaves it unchanged. If there is no match for the lookup condition, the unconnected lookup transformation returns null.
