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Category: ASE: Data Storage
Allocation pages
An allocation page is the first
page
in an allocation unit.
An allocation unit is always created when a
database
is created
(create database)
or space is added to a database
(alter database).
An allocation unit always consists of 256
data pages.
The first page of the first allocation unit always starts with number 0, the last page has the number 255.
The first page of an allocation unit is always called allocation page.
The allocation page of the first allocation unit therefor is page 0. The numbers of all following
allocation pages are a multiple of 256.
The allocation page contains information on the space of
extents,
available on the allocation unit.
The information consists of the
object id,
and the respective
index ids,
the number of free and used pages and the page ids for
table and index
OAM pages.
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