Is it safe to save plain text key prefix?

[mkpankov]

I'm using libreauth::key.
https://docs.rs/libreauth/0.14.0/libreauth/key/index.html

I generate it, hash it using password hashing, save it to the DB and show the key to the user.

Is it cryptographically secure to save plain text prefix of 8 characters to the DB to be able to easily identify the keys? User will then manipulate the keys using prefix instead of DB id.

[breard-r]

Unfortunately, the answer depends on the purpose of the key, which is beyond LibreAuth's scope. The best and only answer I can give is recommend you to get a proper security audit for your project.