Oracle® Database Application Developer's Guide - Rules Manager and Expression Filter 10g Release 2 (10.2) Part Number B14288-01 |
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This section describes new features of Oracle Database 10g Release 2 (10.2) and provides pointers to additional information. New features information from previous releases is also retained to help those users migrating to the current release.
The following section describes the new features in Rules Manager and Expression Filter:
Rules Manager
Rules Manager is a new feature for Oracle Database 10g Release 2 (10.2). Rules Manager uses the Expression Filter and Oracle Object Relational features to give Oracle database the features of a special purpose rules product, but with greater scalability and better operational characteristics.
Expression Filter — cost-based optimizer support for the EVALUATE
operator
The selectivity and the cost of an Expression Filter index are computed when statistics are collected on the expression column, the index, or the table storing expressions. These statistics are stored in the Expression Filter dictionary and they are used to determine the optimal execution plan for the query with EVALUATE
operator.
Expression Filter — attribute set with default values for some attributes
At the time of attribute set creation, default values can be assigned to one or more elementary attributes so that these values are available at the time of expression evaluation. Default values cannot be specified for table alias elementary attributes in the attribute set.
See Also: See the ADD_ELEMENTARY_ATTRIBUTE procedure in Chapter 17, "Management Procedures Using the DBMS_EXPFIL Package" |
Expression Filter — index support for XPath predicates with the Namespace specification