Difference in the implementation of lookup and join
stages,in joining two tables?
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Answer Posted / krishna
Generally we are using lookup for comparision purpose,
based on the reference table size we r using join or lookup.
If the reference table size is less than the main table
then use lookup stage other wise use join stage.
In lookup we have two types:
Normal lookup - reference lookup is less no of rows
compared to main table
sparse lookup - reference lookup is more no of rows
compared to main table.
But the peformance wise use join if the reference table has
more data.
Regards,
Krishna
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