Question

What causes a DB or log files “Initial Size” setting to change? For example, we are trying to shrink a too-large transaction log. We noticed that the “Initial Size” is much larger than is necessary. We can set it lower, but it ends up at the higher value again. Is that the AutoGrowth setting doing that?

Answer 1

The “Initial Size” information actually uses a very misleading header. That should be “Current File Size (MB)” to be more accurate.

Try this:

Choose a database and check the current sizes of the files. Compare that to what you see in the GUI, they should be the same

SELECT file_id, name, physical_name, (size * 8 /1024.0) AS SizeMB FROM sys.database_files

Now increase the file size (I’m using a test database called DBAdmin here)

ALTER DATABASE DBAdmin MODIFY FILE (NAME = dbadmin, SIZE = 1GB)

Run the first query and you’ll see that the SizeMB now reflects that new value, as will the “Initial Size” in the GUI.

Now shrink that file

DBCC SHRINKFILE(1, 500)

And again look at the values from the query and the GUI, you’ll see that they are back at 500MB.

This introduces the question around your transaction log. Are you in simple recovery or full? If in full then increase the frequency of your log backups to help keep the transaction log under control. If in simple recovery then size the transaction log accordingly, do not perform shrink operations on it as it will just need to grow again should the same criteria be met, and the growth portion will introduce a performance hit against your database.