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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "Hive/LanguageManual/DDL" by JohnSichi
Date Thu, 21 Jan 2010 01:09:30 GMT
Dear Wiki user,

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The "Hive/LanguageManual/DDL" page has been changed by JohnSichi.


  A view's schema is frozen at the time the view is created; subsequent changes to underlying
tables (e.g. adding a column) will not be reflected in the view's schema.  If an underlying
table is dropped or changed in an incompatible fashion, subsequent attempts to query the invalid
view will fail.
+ Views are read-only and may not be used as the target of LOAD/INSERT/ALTER.
  A view may contain ORDER BY and LIMIT clauses.  If a referencing query also contains these
clauses, the query-level clauses are evaluated '''after''' the view clauses (and after any
other operations in the query).  For example, if a view specifies LIMIT 5, and a referencing
query is executed as (select * from v LIMIT 10), then at most 5 rows will be returned.
  Example of view creation:

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