hadoop-common-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "Hive/LanguageManual/Transform" by PaulYang
Date Fri, 08 Jan 2010 02:14:32 GMT
Dear Wiki user,

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

The "Hive/LanguageManual/Transform" page has been changed by PaulYang.
http://wiki.apache.org/hadoop/Hive/LanguageManual/Transform?action=diff&rev1=16&rev2=17

--------------------------------------------------

  }}}
  
  == Schema-less Map-reduce Scripts ==
- If there is no ''AS'' clause after ''USING my_script'', Hive assumes the output of the script
contains 2 parts: key which is before the first tab, and value which is the rest after the
first tab.  Note that this is different from specifying ''AS key, value'' because in that
case value will only contains the portion between the first tab and the second tab if there
are multiple tabs.
+ If there is no ''AS'' clause after ''USING my_script'', Hive assumes that the output of
the script contains 2 parts: key which is before the first tab, and value which is the rest
after the first tab.  Note that this is different from specifying ''AS key, value'' because
in that case, value will only contain the portion between the first tab and the second tab
if there are multiple tabs.
  
  Note that we can directly do ''CLUSTER BY key'' without specifying the output schema of
the scripts.
  {{{

Mime
View raw message