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Richard Niemiec

"Oracle Database 10g Performance Tuning Tips & Techniques"


Because the query rewrite clause was not specified during the creation of this materialized
view, the query rewrite capabilities are disabled for the LOCAL_BOOKSHELF table. Fast refresh
capabilities are not supported, because the base table does not have a materialized view log. If
you change your materialized view or its base table, you should regenerate the data in MV_
CAPABILITIES_TABLE to see the new options.
As shown in the preceding listing, the LOCAL_BOOKSHELF materialized view cannot use
a fast refresh because its base table does not have a materialized view log. Here are some other
constraints that will limit your ability to use fast refreshes:
The materialized view must not contain references to nonrepeating expressions such as
SYSDATE and ROWNUM.
The materialized view must not contain references to RAW or LONG RAW datatypes.
For materialized views based on joins, ROWIDs from all tables in the from list must be
part of the select list.
If there are outer joins, all the joins must be connected by ands, the where clause must
have no selections, and unique constraints must exist on the join columns of the inner
join table.
For materialized views based on aggregates, the materialized view logs must contain all
columns from the referenced tables, must specify the rowid and including new values
clauses, and must specify the sequence clause.
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Chapter 17: Managing Distributed Databases 629
See the Oracle Database Data Warehousing Guide 11g Release 1 (11.


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