Groupings
Wednesday, April 27, 2011
2:49 PM
Groupings
A grouping in Bud always has the outcome of creating aggregate data. 
There is no such thing as a Pig grouping that creates hierarchy. 
Example: if 
t1 has schema [:game] => [:player, :score]
then  
totals <= t1.groupby([:player],sum(:score))
has schema [:player]=>[:score]
(Implicitly, the grouped thing becomes a key!) 
Builtin aggregate functions:
count, sum, choose, avg, min, max...