How can I display the patch version?

The command Write $system.Version.GetPatchId()
doesn't show anything.
What other options are there?
Thanks.

How can you find referenced entries in a table that have been deleted with the drop column?
I have to find all fields in the database afterwards and then delete them properly.
Has anyone had this problem yet?
Can the information be found in the class or storage definitions?
Thanks for a quick feedback.