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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Trivial Update of "Hive/LanguageManual/DDL" by SaurabhNanda
Date Mon, 27 Jul 2009 10:26:12 GMT
Dear Wiki user,

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

The following page has been changed by SaurabhNanda:
http://wiki.apache.org/hadoop/Hive/LanguageManual/DDL

The comment on the change is:
Added pointer to CompressedStorage

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  You must specify list of columns for tables with native SerDe. Refer to Types part of the
User Guide for the allowable column types. List of columns for tables with custom SerDe may
be specified but Hive will query the SerDe to determine the list of columns for this table.
  
- Use STORED AS TEXTFILE if the data needs to be stored as plain text files. Use STORED AS
SEQUENCEFILE if the data needs to be compressed. 
+ Use STORED AS TEXTFILE if the data needs to be stored as plain text files. Use STORED AS
SEQUENCEFILE if the data needs to be compressed. Please read more about CompressedStorage
if you are planning to keep data compressed in your Hive tables.
  
  Partitioned tables can be created using PARTIONED BY clause. A table can have one or more
partition columns and a separate data directory is created for each set of partition columns
values. Further tables or partitions can be bucketed using CLUSTERD BY columns and data can
be sorted with in that bucket by SORT BY columns. This can improve performance on certain
kind of queries.
  

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