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Pig, mail # user - Eval UDF passing parameters


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Eval UDF passing parameters
Dexin Wang 2010-12-07, 19:44
Hi,

This might be a dumb question. Is it possible to pass anything other than
the input tuple to a UDF Eval function?

Basically in my UDF, I need to do some user info lookup. So the input will
be:

(userid,f1,f2)

with this UDF, I want to convert it to something like

(userid,age,gender,location,f1,f2)

where in the UDF I do a DB lookup on the userid and returns user's info
(age, gender, etc). But I don't necessarily want to pass back the same user
info fields, e.g. sometimes I only want age.

I hope there is a way for me to tell the UDF that I only want "age", and
sometimes "age, location", etc.

What's the best way to achieve this without having to write a separate UDF
for every case?

Thanks.
Dexin