which is better perfomancewise lookup or joiner and why?can anyone give example?
Answers were Sorted based on User's Feedback
Answer / vijay pal
It depends upon the Situation...
In Homo-genous sources(both the sources are RDBMS), Joiner
has good performance
In Hetro-genous sources (like RDBMS & Flat file) look up
would be better.
But If you want RDBMS data in more than one places, better
go for Lookup than Joiner
Hope it have answered you question :)
| Is This Answer Correct ? | 5 Yes | 3 No |
Answer / 78swapnil
All you guys are correct. But there is a major difference between lookup and joiner is, when you join the table we need to join on the basis of a join condition (=) but in case of lookup you can get the data join conditions like (=,!=,<=,>=).
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / lokesh.t
lookup is having multiple advantages compare to joiner
transformations :-it will avoid duplicate vlues . by
using first last value in lkp values . with lkp we can n
nnumber of tables. where as in joiner we can join only
two tables
| Is This Answer Correct ? | 1 Yes | 3 No |
R u looking for flat or database file?
Generally sorted joiner more effective on flat files than lookup, because sorted joiner uses merge join and cache less rows. Lookup caches always whole file. If the file is not sorted, it can be comparable. Lookups into DB table can be effective if the DB can return sorted data fast and the amount of data is small, because lookup can create whole cache in memory. If DB responses slowly or big amt of data r processed, lookup cache initialization can be really slow.
Then it can be better use sorted joiner, which throws data to output as reads them on input.
| Is This Answer Correct ? | 0 Yes | 2 No |
Answer / m.m.basha
performwise both (connected& unconnected) are best
connected lookup :-it is connected to the source
unconnected loockup:- it is not connected to the source
| Is This Answer Correct ? | 1 Yes | 12 No |
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