MDF Corruption After Transferring Data to Sql_variant Column in SQL Server

MDF Corruption After Transferring Data to Sql_variant Column in SQL Server

When you use DBCC CHECKDB command on SQL database (MDF) file, you may face database inconsistency problems that could cause issues like database corruption. In case of corruption, SQL Server can not recognize the MDF file and thus data stored in it becomes inaccessible. To resolve MDF corruption issues, you need to repair and restore the MDF file using SQL recovery software.

The DBCC CHECKDB command might display error messages due to database inconsistency in your SQL Server database. It takes place when the underwritten conditions are true:

o MS SQL loads data to the column which has a sql_variant data type.

o The data gets created in another column which has a sql_variant data type and the data is sent on-the-wire by the SQL Server.

o Data is sent either to an intermediate file or directly to another database server based on Microsoft SQL Server.

o sql_variant column holds character values.

In case of database inconsistency, SQL Server may not work properly and data stored in the MDF file can not be accessed. Here are some examples of the SQL statements which could result into such behavior:

o A BULK INSERT or BCP statement from the file which was originally created using SELECT statement or BCP IN command from the SQL Server.

o Data load which is using the Data Transforming Services.

o Data load which is using the SQL Server DMO Transfer Object.

In case of MDF file corruption, you may encounter the below given error message:

“Msg 2537, Level 16, State 43, Server MYSERVER, Line 1

Table error: Object ID 1977058079, index ID 0, page (1:75), row 0. Record

check (Valid SqlVariant) failed. Values are 4 and 0.

DBCC results for ‘MyTable’.

There are 0 rows in 1 pages for object ‘MyTable’.

CHECKDB found 0 allocation errors and 1 consistency errors in table.”

In case of corruption, MDF file repair is required to access data from the database. It is best possible using third party SQL Repair software. These software incorporate efficient scanning mechanisms to scan the damaged MDF file and extract all the data from it.

SQL Recovery software are result-oriented and easy-to-use tools that do not require sound or prior technical skills to achieve recovery of your precious data.