The SQL statements available within the Natural programming language comprise two different syntax sets:
Common Set
The Common Set basically corresponds to the standard SQL syntax
definitions and is provided for each SQL-compliant database system supported by
Natural.
Extended Set
The Extended Set, in addition, provides special enhancements to the
Common Set to support specific features of the various
supported database systems. The supported part of the
Extended Set differs with each of these database systems.
The Natural SQL statements documentation mainly describes the Natural SQL Common Set. The statement syntax adheres as far as possible to the syntax described in the relevant literature on SQL; please, refer to this literature for further details. For details on the Natural SQL Extended Set, see the documentation of the Natural interface specific to the database system you use.