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Get rescued from the SQL table corruption

MS SQL database consists of a table which is further divided into rows and columns, and all the records are contained within them. Whenever the administrator or any user wants to retrieve the information from these records then he can run a query. Upon executing the query, the desired information is displayed by the database. But there can be certain instances when you do not receive the desired result and instead of that an error message pops up. However, behind this unexpected behavior there can be several reasons like metadata structure corruption, virus attack, improper system shutdown, application failure, etc.

The error message which is displayed consists of all the required information which is necessary to find out the reason for occurrence of such an error. Let us consider a real-life scenario - a user executes a query to find out the number of rows within the table in SQL database. For this, the user executes count (*) query but in spite of displaying the result, an error message pops up:

"Attempt to fetch logical page (1:42724) in database 'test' belongs to object 'report-table', not to object 'RRR'. Connection Broken"

After encountering this problem, the user thinks that the table is corrupted and to examine the level of corruption he executes the DBCC Checktable command with repair_rebuild parameter. As a result, the following message is displayed:

"Server: Msg 2535, Level 16, State 1, Line 1
Table Corrupt: Page (1:42724) is allocated to object ID 1517248460, index ID 0, not to object ID 982294559, index ID 0 found in page header.
Server: Msg 8928, Level 16, State 1, Line 1
Object ID 1517248460, index ID 0: Page (1:42723) could not be processed. See other errors for details.
Server: Msg 8939, Level 16, State 1, Line 1
Table Corrupt: Object ID 1517248460, index ID 0, page (1:42723). Test (m_freeCnt == freeCnt) failed. Values are 1468 and 8066.
Server: Msg 8939, Level 16, State 1, Line 1
Table Corrupt: Object ID 1517248460, index ID 0, page (1:42723). Test (emptySlotCnt == 0) failed. Values are 15 and 0………"

After the occurrence of above message, the table turns completely inaccessible. The user even executes DBCC CHECKDB command with repair_allow_data_loss paramater but no solution comes out to be fruitful. In such a scenario, the user can only perform restoration of the entire SQL database from an already maintained backup so as to retrieve the information and records yet again.

But, in case the user or administrator has not maintained a backup then in that scenario a commercial SQL data recovery solution would be required to do the needful. In this regard, Kernel for SQL is one of the most proficient and advanced software amongst the plethora of such software available in the market. It is embedded with QFSCI algorithm that performs efficient recovery of tables, views, triggers, primary keys, unique keys, foreign keys, stored procedures, etc. Moreover, the software also performs recovery of corrupt SQL server databases. To evaluate the software before purchase, you are advised to try its free demo version.   

For more information:-  http://www.sqldatabaserecovery.org