default_spec

< default_spec > ::=
  DEFAULT <
literal >
| DEFAULT NULL
| DEFAULT USER
| DEFAULT USERGROUP
| DEFAULT SYSDBA
| DEFAULT DATE
| DEFAULT TIME
| DEFAULT TIMESTAMP
| DEFAULT UTCDATE
| DEFAULT UTCDIFF
| DEFAULT TIMEZONE
| DEFAULT TRUE
| DEFAULT FALSE
| DEFAULT TRANSACTION
| DEFAULT STAMP
| DEFAULT SERIAL[(<
unsigned_integer >)]