Wednesday, February 24, 2016

Difference Between Normal Lookup and Sparse Lookup

Difference Between Normal Lookup and Sparse Lookup


Normal Lookup :- 
  • Normal Lookup data needs to be in memory
  • Normal might provide poor performance if the reference data is huge as it has to put all the data in memory.
  • Normal Lookup can have more than one reference link.
  • Normal lookup can be used with any database
Sparse Lookup :- 
  • Sparse Lookup directly hits the database.
  • If the input stream data is less and reference data is more like 1:100 or more in such cases sparse lookup is better.
  • Sparse Lookup,we can only have one reference link.
  • Sparse lookup,we can only use for Oracle and DB2.
  • Sparse lookup sends individual sql statements for every incoming row.(Imagine if the reference data is  huge).
This Lookup type option can be found in Oracle or DB2 stages.Default is Normal

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