From the MySQL manual:
That's MySQL speak for "yeah, we released something that can break your application and potentially open it up to hackers, so uhm... just don't use it, ok?It'll be fine..."
ALTER USERwas added in MySQL 5.6.6. However, in 5.6.6,
ALTER USERalso sets the
Passwordcolumn to the empty string, so do not use this statement until 5.6.7.
In PostgreSQL, features are either completed before release, or they are made safe by giving an error message when the incomplete part is accessed.
These hidden "features" that can cost hours of debugging and restoring and, potentially, a large data-leak, simply don't exist in PostgreSQL.