Oracle in a Nutshell

Name

Physical_Attributes_Clause

Synopsis

[INITRANS integer]
[MAXTRANS integer]
[PCTFREE integer]
[PCTUSED integer]

Specifies schema object characteristics affecting space utilization in an Oracle block.

Keywords

INITTRANS

Specifies the number of transaction entries allocated to each block of the object. The allowed range of values is 1 to 255 and should not normally be changed from the default of 1 (although a value as high as 4 to 8 may be beneficial for an OLTP system with a high transaction rate).

MAXTRANS

Specifies the maximum number of concurrent transactions that can update a block of the object. Values are 1 to 255 and should not normally be changed from the default. The default is a function of the Oracle block size.

PCTFREE

Specifies the percentage of space in each data block kept free for future updates to the object. The permissible range of values is 0 to 99. The default value is 10.

PCTUSED

Specifies the percentage of space in each data block that Oracle attempts to keep filled. The permissible range of values is 0 to 99, and the default is 40. Note that this keyword does not apply to indexes.