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From Apache Wiki <wikidi...@apache.org>
Subject [Pig Wiki] Update of "PigLatin" by EdChi
Date Sun, 07 Sep 2008 02:16:16 GMT
Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Pig Wiki" for change notification.

The following page has been changed by EdChi:
http://wiki.apache.org/pig/PigLatin

The comment on the change is:
fixed typo

------------------------------------------------------------------------------
  
  [[Anchor(Nested_Operations_in_FOREACH...GENERATE)]]
  ==== Nested Operations in FOREACH...GENERATE ====
- If one of the fields in the input relation is a data bag, the nested data bag can be treated
as an '''inner''' or a '''nested relation'''. Consequently, in a FOEACH...GENERATE statement,
we can perform many of the operations on this nested relation that we can on a regular relation.

+ If one of the fields in the input relation is a data bag, the nested data bag can be treated
as an '''inner''' or a '''nested relation'''. Consequently, in a FOREACH...GENERATE statement,
we can perform many of the operations on this nested relation that we can on a regular relation.

  
  The specific operations that we can do on the nested relations are [#FILTER:_Getting_rid_of_data_you_are_not_interested_in_
FILTER], [#ORDER:_Sorting_data_according_to_some_fields ORDER], and [#DISTINCT:_Eliminating_duplicates_in_data
DISTINCT]. Note that we do not allow FOREACH...GENERATE on the nested relation, since that
leads to the possibility of arbitrary number of nesting levels. 
  

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