what is the difference between the join and look up
explin me one exmple
Answer Posted / ankit gosain
Difference Between Join & Lookup:
1. In join stage you can do Inner Join, Left outer, Right
Outer and Full outer join, while in Lookup stage you can do
Inner join & Left outer join only.
2. In join stage you can't have a reject link, while in
lookup stage you can have a reject link for Unmatched
Primary records.
3. In join stage sorted data is mandatory, while in lookup
stage sorted data is not mandatory for lookup source.
4. Join stage requires Hash Partitioned data, while lookup
stage requires Entire partitioned lookup data.
5. In case of Join, Disk I/O is more while it's very less
in case of lookup (since at the time of matching, complete
lookup data is present in the memory).
6. In case of Join Stage, the key column name must be the
same in both the sources, while in case of lookup stage
it's not mandatory.
Cheers,
Ankit :)
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