Apache Hive Cookbook by Hanish Bansal & Saurabh Chauhan & Shrey Mehrotra

Author:Hanish Bansal & Saurabh Chauhan & Shrey Mehrotra [Bansal, Hanish]
Language: eng
Format: azw3
Publisher: Packt Publishing
Published: 2016-04-29T04:00:00+00:00

Hive supports only non-materialized views and as it does not support materialized data, the view is strictly bound to the tables it is based on. In other words, it also means if the columns of the tables are altered or dropped, it would affect the view or even fail the view.

How to do it…

These views are the logical constructs that do not store data with them. When a view is created in Hive, the underlying query is stored in the metastore. When the view is queried, the view's clauses or conditions are evaluated before the underlying query clause. For example, if the query has a limit of 200 and the view has a limit of 100 then the query would return 100 results.

An example of a view definition is as follows:

CREATE VIEW sales_view AS SELECT * FROM SALES WHERE ip = '192.168.56.101' or ip='192.168.56.106';

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