md5 hashing using password as salt?

Question

md5($password.md5($password))

is this good enough for password hashing? I am not asking for comparing this to something like bcrypt.

if it

Answer 1

The reason why random password salt is recommended for hashing password, so that an attacker who knows the password hash can't compare it to rainbow table of pre-calculated hashed from dictionary.

If you're using password as salt, attacker can pre-calculate hashes of $word.md5($word) first from their dictionary