How to keep the local file or the remote file during merge using Git and the command line?

You can as well do:

git checkout --theirs /path/to/file

to keep the remote file, and:

git checkout --ours /path/to/file

to keep local file.

Then git add them and everything is done.

Edition: Keep in mind that this is for a merge scenario. During a rebase --theirs refers to the branch where you've been working.

This approach seems more straightforward, avoiding the need to individually select each file:

# keep remote files
git merge --strategy-option theirs
# keep local files
git merge --strategy-option ours

or

# keep remote files
git pull -Xtheirs
# keep local files
git pull -Xours

Copied directly from: Resolve Git merge conflicts in favor of their changes during a pull

git checkout {branch-name} -- {file-name}

This will use the file from the branch of choice.

I like this because posh-git autocomplete works great with this. It also removes any ambiguity as to which branch is remote and which is local. And --theirs didn't work for me anyways.