why we use hash file for lookup?
Answers were Sorted based on User's Feedback
Answer / hari
Hash partitioning
method is the key
based partition
method... And lookup
wich also compare and
retrieve the data
based on key
column... So by using
hash method wil
increase performance
in lookup...
Is This Answer Correct ? | 5 Yes | 0 No |
Answer / jayam
Hash file is worked in key based . so lookup stage work on
comparasion of columns. so using hash file
Is This Answer Correct ? | 3 Yes | 0 No |
Answer / bharath
Hash file is a refference table based on key fileds which
can provide fast access in lookups. Just to spped up the
lookup process we use hash files.
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / varma
Hash files is the only way to do lookup .. It is key based
and ensures no duplicates are present on that key. It wont
give an error if you use OCI or DB2 stage as lookup but the
results will be wrong...
Is This Answer Correct ? | 1 Yes | 0 No |
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