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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "Hive/LanguageManual/LateralView" by PaulYang
Date Thu, 14 Jan 2010 03:01:11 GMT
Dear Wiki user,

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The "Hive/LanguageManual/LateralView" page has been changed by PaulYang.
http://wiki.apache.org/hadoop/Hive/LanguageManual/LateralView?action=diff&rev1=2&rev2=3

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  == Description ==
  
- Lateral view is used in conjunction with user-defined table generating functions such as
explode(). As mentioned in [wiki:Self:Hive/LanguageManual/UDF#UDTF], a UDTF generates one
or more output rows for each input row. A lateral view constructs a virtual table by applying
the UDTF to each row of base table and using the resulting output rows to form a virtual table
having the supplied table alias. In addition, each input row from the base table is joined
with the respective output rows in the virtual table.
+ Lateral view is used in conjunction with user-defined table generating functions such as
explode(). As mentioned in [wiki:Self:Hive/LanguageManual/UDF#UDTF], a UDTF generates one
or more output rows for each input row. A lateral view first applies the UDTF to each row
of base table and then joins resulting output rows to the input rows to form a virtual table
having the supplied table alias. 
  
  == Example ==
  

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