New Partitioning Features


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Changes to alter materialized view log Command

A force parameter has been added to the alter materialized view log command. This causes Oracle Database 10g to ignore any items in the add clause that have already been defined in the Mview log. Oracle Database 10g simply ignores the error, and any items in the command that can be added will be added. Some conditions will still cause errors to be signaled, however, such as if you improperly define a tablespace.

The dbms_dimension Package

The dbms_dimension package is new for Oracle Database 10g. This package offers new functionality to help you manage dimensions. You can use the procedure dbms_dimension.describe_dimension to extract the definition of a dimension. Also, the dbms_dimension.validate_dimension procedure allows you to validate dimensions (this is similar functionality to the dbms_olap.validate_dimension procedure).

New Partitioning Features

Oracle Database 10g comes with a number of new partitioning enhancements:

image Index-organized table partitioning improvements

image Hash-partitioned global indexes

image Partitioned index maintenance

image Skipping unusable indexes

Index-Organized Table Partitioning Improvements

If you use index-organized tables (IOTs), you might well be interested in some new partitioning features related to IOTs. First, prior to Oracle Database 10g, you could not use list partitioning with IOTs. This restriction has been removed. Note that an IOT still cannot be partitioned using composite partitioning.

In Oracle Database 10g, global maintenance (e.g., drop or exchange partition operations) of an IOT will not result in the indexes being marked as unusable. Instead, Oracle now maintains the indexes during the maintenance operation and maintains the UROWIDs associated with the IOTs.

If you create a mapping table on a partitioned IOT, the mapping table will be partitioned if the IOT is partitioned and those partitions will share the same name and physical attributes as the base IOT partitions. Finally, prior to Oracle Database 10g, certain types of partitioned IOT's could not contain LOB columns (e.g. hash partitioned tables). This restriction has been removed in Oracle Database 10g.


Oracle Database 10g New Features
Oracle Database 10g New Features (Osborne ORACLE Press Series)
ISBN: 0072229470
EAN: 2147483647
Year: 2006
Pages: 80

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