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How an Oracle block# is mapped to a file offset (in bytes or OS blocks) (Doc ID 761734.1)

Last updated on AUGUST 04, 2018

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 10.2 to 12.1]
Information in this document applies to any platform.


This document is about how an Oracle block number is mapped to a file offset (in bytes or OS blocks) for Generic OS platforms and includes an alternate formula for specific OS platforms like AIX and HP Tru64. These are the only 2 platforms where the Volume Manager reserves space for Metadata in the Oracle datafile.

For Oracle 10g and 10gR2 there are only two platforms with logical volume Metadata on raw devices: AIX and HP Tru64.

HP Tru64 is no longer supported on Oracle 11g, so AIX is the only one in 11g.


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In this Document
 Generic Platform Formula:
 Alternate Platform Specific Formula (i.e. AIX and HP Tru64):

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