HIVE-14495. Since the number of materialized views in the system might grow very large, and query rewriting using materialized views might be very expensive, we need to include a mechanism to enable/disable materialized views for query rewriting.
Thus, we should extend the CREATE MATERIALIZED VIEW statement as follows:
CREATE MATERIALIZED VIEW [IF NOT EXISTS] [db_name.]materialized_view_name
[ENABLE REWRITE] [COMMENT materialized_view_comment]
[ROW FORMAT row_format]
[STORED AS file_format]
| STORED BY 'storage.handler.class.name' [WITH SERDEPROPERTIES (...)]
[TBLPROPERTIES (property_name=property_value, ...)]