Why we use lookup transformations?

Lookup Transformations used to search data from relational tables/FLAT Files that are not used in mapping.
Types of Lookup:
1. Connected Lookup
2. UnConnected Lookup

 

What is Source Qualifier in Informatica

source qualifier will read data from sources.
for reading data from sources sql is mandatory

 

Where does the records goes which does not satisfy condition in filter transformation?

It goes to the default group. If you connect default group to an output, the powercenter processes the data. Otherwise, it doesnt process the default group.

 

How can U create or import flat file definition in to the warehouse designer?

U can not create or import flat file defintion in to warehouse designer directly.Instead U must analyze the file in source analyzer,then drag it into the warehouse designer.When U drag the flat file source defintion into warehouse desginer workspace,the warehouse designer creates a relational target defintion not a file defintion.If u want to load to a file,configure the session to write to a flat file.When the informatica server runs the session,it creates and loads the flatfile.

 

How do you identify existing rows of data in the target table using lookup transformation?

There are two ways to lookup the target table to verify a row exists or not :
1. Use connect dynamic cache lookup and then check the values of NewLookuprow Output port to decide whether the incoming record already exists in the table / cache or not.

2. Use Unconnected lookup and call it from an expression trasformation and check the Lookup condition port value (Null/ Not Null) to decide whether the incoming record already exists in the table or not.

 

Can any one tell why we are populating time dimension only with scripts not with mapping?

becuase time dimension is rapidly changing dimenction. if you use mapping it is very big stuff and that to be it very big problem in performence wise.

 

What r the different options used to configure the sequential batches?

Two options

Run the session only if previous session completes sucessfully. Always runs the session.

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