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The "Hive/PartitionedViews" page has been changed by JohnSichi.
http://wiki.apache.org/hadoop/Hive/PartitionedViews

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New page:
This is a followup to [[Hive/ViewDev]] for adding partition-awareness to views.

= Use Cases =

* An administrator wants to create a set of views as a table/column renaming 
layer on top of an existing set of base tables, without disturbing the ETL 
processes which load those tables.  To read-only users, the views should behave 
exactly the same as the underlying tables in every way.  Among other things, 
this means users should be able to browse available partitions.
* A base table is partitioned on columns (ds,hr) for date and hour.  Besides 
this fine-grained partitioning, users would also like to see a virtual table of 
coarse-grained (date-only) partitioning in which the partition for a given date 
only appears once all of the hour-level partitions of that day have been fully 
loaded.
* A view is defined on a complex join+union+aggregation of a number of 
underlying base tables and other views, all of which are themselves 
partitioned.  The top-level view should also be partitioned accordingly, with a 
new partition not appearing until corresponding partitions have been loaded for 
all of the underlying tables.

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