You misunderstand the issue. The length of the password should not have any effect on the size of the database field. The fact that it apparently does is a huge red flag. You hash the password and store the hash in the db. For example, a sha256 hash is always 32 bytes long, no matter how much data you feed into it (btw, don’t use sha256 to hash passwords, it was just an example. It’s not a suitable password hashing algorithm as it’s not slow enough).