Index Property Sheet: Storage Page

Two methods are provided for defining storage parameters:

• Explicit (default setting ): User specifies all storage parameters for the index.

• Auto Calculation: Schema Manager calculates optimum storage parameters using methods recommended in the Oracle8i AdministratorĖs Guide. However, auto-calculation does not apply to spatial indexes.

Initial Size: Size of the object's first extent. You can enter a value, the minimum being the size of one data block. The default value is the size of five data blocks.

Next Size: Size of the next extent to be allocated to the object. The default value is the size of five data blocks. The smallest permissible value is the size of one data block.

Increase Size by: Percent by which each extent grows (after the second extent) compared to the previous extent.

Minimum Number: Total number of extents allocated when a segment is created. The default value is one. You can enter a value of one or greater.

Maximum Number: Total number of extents, including the first, that an Oracle database can allocate for the object. There are two extent options available, Unlimited and Value.

• Unlimited: When selected, allows you to create a number of extents that is only limited by the amount of contiguous free space in a tablespace.

• Value: When selected, allows you to specify the maximum number of extents. If you do not specify a value, the default value applies. The default and maximum values depend on the data block size. You can enter a value of one or greater. The default value varies.

% Free: Percentage of space in each of the object's data blocks that is reserved for future updates to the object. You can enter values from 0 to 99.

% Used: Minimum percentage of used space that an Oracle database maintains for each data block of the object. A block becomes a candidate for row insertions when its used space falls below the % Used value. You can enter a value from 1 to 99. The default value is 40.

Number of Transactions

Initial: Initial number of transaction entries allocated within each data block allocated to the object. You can enter a value from 1 or 2 (for clusters and indexes) to 255.

Maximum: Maximum number of concurrent transactions that can update a data block allocated to the object. You can enter a value from 1 to 255.

Free Lists

Lists: Number of free lists for each of the free list groups for the table, cluster, or index. You can enter a value of one or greater. The default value is 1.

Groups: Number of groups of free lists for a table, cluster, or index. You can enter a value of one or greater. The default value is 1.

See also: Main topics (outline)