Hi,
I have a confusion, what is the main difference between Lookup and Join Stage.
Regards,
Vinodn
Difference Between Lookup and join stage
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please find the below inforamtion which differentiates JOINS LOOK UP and MERGE stages.
may be bit tough to read(format)..
u can follow the below example for reading ...
model for joins is RDBMS,model for look up is RAM LU table and model for merge is Master-update
JOINS LOOK UP MERGE
MODEL RDBMS-Style relational , Source-in RAM LU table , Master-Update(s)
MEMORY light , heavy , light
# AND NAMES OF INPUT "2 or more:left,right" , "1 source ,N LU tables" , 1 Master N update(s)
MANDATORY INPUT SORT both inputs , no , all inputs
DUPLICATES IN PRIMARY INPUT ok(x-product) , ok , warning!
DUPLICATES IN SECONDARY INPUT ok(x-product) , warning! , ok when only N=1
OPTIONS ON UNMATCHED PRIMARY "keep(left outer),drop(inner)" ,[fail] continue|drop|reject , [keep]|drop
OPTIONS ON UNMATCHED SECONDARY "keep(right outer),drop (inner)" , none , capture in reject set(s)
OUTPUTS 1 , "1 out ,1 reject" , "1 out,n rejects"
CAPTURED IN REJECT SETS nothing , unmatched primary entries , unmatched secondary entries![Smile :)](./images/smilies/icon_smile.gif)
may be bit tough to read(format)..
u can follow the below example for reading ...
model for joins is RDBMS,model for look up is RAM LU table and model for merge is Master-update
JOINS LOOK UP MERGE
MODEL RDBMS-Style relational , Source-in RAM LU table , Master-Update(s)
MEMORY light , heavy , light
# AND NAMES OF INPUT "2 or more:left,right" , "1 source ,N LU tables" , 1 Master N update(s)
MANDATORY INPUT SORT both inputs , no , all inputs
DUPLICATES IN PRIMARY INPUT ok(x-product) , ok , warning!
DUPLICATES IN SECONDARY INPUT ok(x-product) , warning! , ok when only N=1
OPTIONS ON UNMATCHED PRIMARY "keep(left outer),drop(inner)" ,[fail] continue|drop|reject , [keep]|drop
OPTIONS ON UNMATCHED SECONDARY "keep(right outer),drop (inner)" , none , capture in reject set(s)
OUTPUTS 1 , "1 out ,1 reject" , "1 out,n rejects"
CAPTURED IN REJECT SETS nothing , unmatched primary entries , unmatched secondary entries
![Smile :)](./images/smilies/icon_smile.gif)
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Use Code tags for fixed-width format.shiva_reddys447 wrote:please find the below inforamtion which differentiates JOINS LOOK UP and MERGE stages.
may be bit tough to read(format)..
Were you aware that IBM owns copyright in the manuals?
Why are you advocating that U follow the example? U did not ask the question.
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Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.
Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.
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Re: Difference Between Lookup and join stage
There are many differences. Who are we to decide which is the main one?vinodn wrote:what is the main difference between Lookup and Join Stage.
Is this an interview question?
They are different. That's enough. A spanner and a wrench are different, though they perform similar tasks. What the main difference between them? You choose the right tool for the job at hand.
IBM Software Services Group
Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.
Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.