Origin of Error Message:
When there is a discontinuation at some point in B-tree chain of logical pages; the error message takes place on the SQL database. The error occurred due to this situation is categorized as SQL error 8936 and resembles similar to this:
Severity Level 16
Message Text
Table error: Object ID O_ID, index ID I_ID. B-tree chain linkage mismatch. P_ID1->next = P_ID2, but P_ID2->Prev = P_ID3.
This error message indicates that the pointer of "Page P_ID1" points to the page ID "P_ID2" but this page points to page "P_ID3".
As a resolution to this problem, you can follow various procedures that are summed up herein:
Solution#1: Hardware Diagnostics:
By running the hardware diagnostics in Windows 7 or 8, the root cause can be detected if it is related to some hardware component. Hardware Diagnostic Tool is located at different locations in different version of Windows and the destination storage depends on the system's brand as well. The following section can be referred to for knowing the storage location as per make.
"Start > All Programs > PC Help and Tools > Hardware Diagnostic Tools"
Therefore, diagnostic tool can be run to detect the hardware related issues and can further be resolved accordingly.
Solution#2: Restore from Backup:
Since, the records incorporated in the SQL databases are immense importat, it is highly recommended to backup DB on regular basis. So that, if anything unexpected happens such as SQL error 8936; the affected database can be restored back from BAK files. It is a good practice to save the backup files at off-site storage location rather than saving them at on-premises device.
Points to Remember While Backup Restoration:
Solution#3: Execute Database Console Commands:
In case there is no backup available, the affected database can be recovered using DBCC. The syntax that can be used to repair DB is;
While executing DBCC, it is recommended to first run it without any repair clause. As a result it will display the appropriate clause and this recommended clause can be used to run DBCC further. This may help in rectifying the issue.
Points to Remember While Executing DBCC:
Following points must be taken into consideration while implementing database repair commands:
Although, backup restoration and DBCC commands are helpful database recovery solutions but these methods requires sound technical expertise and are time taken as well. To ensure fast and instant recovery of SQL DB; you can implement one-step solution that have been discussed in the upcoming section.
If in any case, you notice any loss of information or if the DB components get damaged during the repair process, you can utilize below mentioned recovery procedure that will help you to recover the database files and help restoring lost data while rectifying SQL error 8936.
SQL recovery is an alternate approach that ensures safe and quick recovery of SQL databases from all kind of errors whether they belong to MDF or NDF files. In addition, it successfully restores corrupt as well as deleted components from database files in an instant manner.