MS SQL Server, though considered one of the most reliable Relational Database Management System as it works appropriately most of the times, but also suffers corruption issues at some point of time. In such situations the primary storage i.e. MDF file fails to open, thereby restricting the accessibility of the stored data items. Together with that, the associated secondary data (NDF) file items may also get damaged (if present) and hence inaccessibility of its data items may occur as well. One error that is related to corruption scenario in the database file is SQL error 2537. This particular article gives detailed information about the cause of the error and the way it can be fixed.
Overview: When the SQL database is tried to be mounted, it fails and error 2537 occurs with Severity Level – 16 and below given text message:
Table error:Object ID O_ID, index ID I_ID, page P_ID, row ROW_ID. Record check (CHECK_TEXT) failed. Values are VALUE1 and VALUE2.
Expaination: Either the row ROW_ID or a column in the row failed the examination or state illustrated by CHECK_TEXT. The interpretation of VALUE1 and VALUE2 depends on the error state. SQL server error 2537 can exhibit different state such as State 40, 43, 100, 101, 401, 510, 511, 512 and 513
Cause: The cause of many SQL errors is either corruption in MS SQL server database table or in complete database (MDF and NDF file), which in turn are caused by attack of viruses, hardware failure, improper machine shutdown, network issues, damage in metadata structure, etc. However, the two major causes for occurrence of SQL error 2537 are as follows:
Although the error suggests executing the REPAIR_ALLOW_DATALOSS statement on damaged database files, it should not be run as it is most probable that the stored data might get lost. Therefore, other ways should be brought in use to fix the error and get back access to the database items. Some of the suitable methods are described herein.
Correct Hardware Issues: It is quite possible that CHECK_TEXT may fail because of hardware related issues. Hence, the SQL log entries and the MS Windows NT system as well as its application logs should be tested by running the hardware diagnostic tool.
If any problem is found then the particular damaged hardware component or the entire system should be replaced. It should also be checked if the write caching is disabled on the system or not and if not then a hardware vendor should be contacted to disable it. If corruption is not related to hardware then the below ways can be implied upon.
Backup Restore: One of the best ways to recover the data items is to restore database backup as it is easy and effective methods to retrieve the MDF and NDF file data. But if backup has not been created or has itself become damaged then other methods as explained below can surely be resorted to.
Execute DBCC CHECKDB: DBCC CHECKDB is an in-built utility provided for repair of database file in case of logical corruption issues. At first it is recommended that the command be run without a repair clause to determine the amount of corruption. Then, the command can be executed with a repair clause so that corrupted file can be repaired.
However, the command poses a threat to the data of primary and secondary file of SQL database. One of the most serious drawbacks is that the command causes data loss and has some bad effects. The effects are state-dependent as explained below:
Note As the DBCC CHECKDB command does not prove to be an apt solution, any third party commercially available software applications should be brought in use.
A professional application has been uniquely designed and developed to fix all kinds of corruption issues and recover MDF file. Inclusive of many advanced features, the software is capable enough to fix SQL server error 2537 and almost all other errors that occur due to damage in the server database file. Some of the tool's characteristics are as follows: