In SQL Server, if the MDF/NDF file gets corrupted, it can be fixed with the help of the SQL Server Management Studio. It can be used by the users to fix the database. When you run the repair procedure, the database will be fixed and the users can use it.
To avoid this problem, the SQL Server can not truncate the log file immediately after a crash. Instead, the SQL Server will start a repair process on the log file, which will ultimately finish in a few minutes. Because repairing the log file is a time-consuming operation, this situation can cause Read Locks on the log file, and if the log file becomes too large, it can prevent the application from writing to the log file.
Check Table and Column Roles: If you have any database table that contain columns with default constraints, you must check the table and column roles. The column role is an object-level attribute for each column in a table. The system stores information about the default property for every column in the table. For example, if you have a table with columns A, B, and C, and if you use the default value of B = 99 for column B, the system automatically stores a default constraint of 99 on the column B. If you set the column B to NULL, the default constraint of 99 cannot be set.
In Windows, there are two types of MDF files, depending on where they are stored on disk:
Local MDF files, which are stored in the same directory as the MDF file. Local MDF files are created and deleted by SQL Server.
System MDF files, which are stored at the root level of the Windows directory tree. System MDF files are created by the SQL Server installation process, and SQL Server deletes them when the database is removed.
The process of recovering from a system crash is usually fairly quick, but can take considerable time, depending on the number of transactions still in progress. As a result, it is usually not practical to wait for a recovery to complete before shutting down and restarting the server. The risk of data loss due to a crash is greater than the risk of data loss during server restarts. 827ec27edc