version control - How to Tag a single file in GIT

Question

I am very new to git. I am currently trying to get familiarized with it by using it to track changes in some excel files that I am maintaining to track some continuous activity I am involved with. All the files are in a single repository. I want to tag each file separately with their versions. Is this possible? So far what I found was the capability to tag the entire repository. If what I am trying to do is wrong, do advise me on the best practice.

Thanks in advance.

Edit

When I was doing this I deliberately deleted a previous tag to make the entire repository be tagged( as I did not find a way to tag single files) as v1.0. As I now want to reset the name of the tag with the file name and quite comfortable with the way things should happen, how can I rollback the deletion and rename the previous tag (the deleted tag)?

Answer 1

Technically you can tag the content of a single file without it's file name. But such tags are of limited use. Tags are expected to point to commits, and special tags to non-commits have very different behavior (you can't git checkout such a special tag). So I strongly suggest to never use non-commit tags.

When you want only some files to be tagged, it might be better to use a separate repo for them, or at least different branches, since git always looks at the full tree for it's operations.

If you still insist to create such a special tag you do:

> git ls-tree HEAD
040000 tree 2c186ad49fa24695512df5e41cb5e6f2d33c119b    bar
100644 blob 409940768f2a684935a7d15a29f96e82c487f439    foo.txt

> git tag my-bar-tree 2c186ad49fa24695512df5e41cb5e6f2d33c119b
> git tag my-foo-file 409940768f2a684935a7d15a29f96e82c487f439