PFS (Page Free Space) pages in SQL Server database
not only maintains free spaces, but a lot more than
that. Every SQL database file is divided into various
PFS intervals, each containing 8088 pages. A PFS page
contains a byte-map, which stores one byte for every
page included in the PFS interval. Corruption in PFS
page results into damage in the stored bytes, further
resulting in making your database nmountable. However,
in case of backup unavailability or corruption, you will
need to use a third-party MS SQL Repair tool, which
provides systematic repair.
As a practical example, you receive the below error
message while mounting your SQL database:
"Database error: Page P_ID1 is marked with the wrong
type in PFS page P_ID2. PFS status 0xVAL1 expected
0xVAL2."
The appearance of the above error message makes your
database unmountable, further resulting into
inaccessibility of its stored records.
Cause
The above error message appears when the below bits
are improperly set:
PFS_IS_IAM_PG (0x10)
PFS_IS_MIXED_EXT (0x20)
PFS_IS_ALLOCATED (0x40)
Damage in PFS pages can occur either due to logical
or physical reasons.
Resolution
To read your database records and to resolve the
error message, you will need to follow the below
measures:
If the above error arises due to physical damages, then
you have to swap the damaged system component with a new
component. However, if the message arises due to logical
corruption, then you will need to run DBCC CHECKDB, with
appropriate repair clause.
While the first resolution provides 100% guarantee to
resolve all physical damages. For such cases, only a
third-party SQL Repair application should be used. These
mdf repair utilities systematically scans a logically
corrupted database and restores it on default or new
destination. Such repair software are self-explanatory
and can be very easily used by even non-technical users.
SQL Recovery supports repairing of SQL databases
created in SQL Server 2008, 20005, and 2000. The
SQLl repair application does not modify or overwrite
the original content stored in the database file. The
repair software supports Windows 7, Vista, XP, 2003,
2000 and NT.
Adishree Singh work as a freelancer and researcher
repair SQL database &
repair SQL software.
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