what is the main differences between Lookup, Join and Merge
stages?

Answer Posted / rahul

all the three stages are differ with each other mainly
depends on three categories

1)input column requirements
a) sorting
b)de duplication
2)treatment of unmatched data
3)memory usage

1.. sorting in joins and merge in primary table and
secondary table is mandatory where in look up its optional.
de duplication in joins its allowed no warnings and no
job aborts.
in case of look up in primary table its accepted but in
secondary it raises warnings.
in merge primary table raises warnings in secondary
table its accepted.


about treatment of unmatched data and about memory discussed
above by some one..


thank you

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