Introduction
You may see it more commonly referenced as Database Instance File Initialization (DIFI). If you are not familiar with the file initialization, this is the process SQL Server has to go through when it is creating the data files for a given database, and also during an expansion event (either manually or from auto growth) for a database. It only pertains to the data file(s) of the database, as log files are not affected by this security policy. SQL Server will “zero out” the file, basically fill it up with a bunch of zeros to allocate the amount of space requested. If you are a new DBA, this configuration actually goes all the way back to SQL Server 2005.
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