Oracle error messages can sometimes be quite annoying and sometimes seem to have nothing to do with the problem. The other day in fact, my Data Guard standby wouldn’t come up complaining about the system data file not being restored from an old enough backup (when it was an active duplication to standby) – the problem was actually an invalid hostname in the tnsnames.ora (yes, really).
Well, Oracle deserves kudos for this one (thanks to Kevin D. for showing me this):
[oracle@server ~] oerr ora 2430 02430, 00000, "cannot enable constraint (%s) - no such constraint" // *Cause: the named constraint does not exist for this table. // *Action: Obvious