I want to make db_name=boston, not keep it as the same as primary=chicago. Is this valid configuration?NO. DB_NAME must be the same ("chicago") at both sites. The Standby will be using a different DB_UNIQUE_NAME (e.g. "boston") and can be using a different Instance name / SID (e.g. "boston").
can I rename datafilesYes. The database file names can be changed.
If I don't use primary DB backup. Instead, I copy all datafiles, redo_log files (no control files) to standbyWhat is the difference between the first sentence (a backup of the primary) and the second sentence (a copy of the primary) ? A Copy is a backup.