Hi Ton!

This question goes a bit deeper into the architecture of SQL server. I'll try to tell you in simple words, hopefully still correct, but it should give you the idea.

Unallocated space is storage that has been allocated to the database, but not yet to a specific object. Imagine you have a barrel that can contain 100 litres of whatever, but you have only 10 litres filled in. So you can still add 90 litres.

When there is no more unallocated space, SQL Server will grow the file - in your case, up to 500 MB. If you come to this limit, DNN will not work anymore, as it cannot write anything to the database, but I think it's a long way until you reach that.

And yes, you can shrink the files, but this could cause issues as well. I don't see the need for that, unless you have to pay less when your file is 300 MB smaller.

Happy DNNing!
Michael

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