The United States government has adopted ANSI X3.135-1989,
Database Language SQL, as the database
language to be used by all federal departments and agencies. This SQL
standard, known as Federal Information Processing Standard 127.1 (FIPSPUB 127.1),
requires that an option be provided which flags all features or extensions
that do not conform to the SQL language or
are processed in a nonconforming manner.
FIPS 127.1 also has added an optional integrity enhancement feature,
addendum 1, to X3.135-1989. Addendum 1 includes referential
integrity constraints, a check clause, and a default clause.
A feature does not have to be flagged if it conforms
to addendum 1.
The SQL standard does not contain functionality for many common categories,
such as storage management and index creation. While many of these
non-standard features are useful, they can reduce
the portability of programs that use them. Most SQL implementations
(including ALLBASE/SQL) support implementation-defined features that do not
conform to FIPS 127.1.
These non-standard implementation features are of concern to users who want
to port programs and who need to identify features that do not conform to FIPS 127.1. In order to recognize features and extensions that do not conform to the
SQL standard, FIPS 127.1 requires that a flagger capability be implemented that
identifies any non-standard features. This flag can be implemented
through software or in documentation. In addition to this appendix, ALLBASE/SQL
provides flagger options for preprocessing and a SET FLAGGER command
in ISQL.
Refer to the ALLBASE/SQL Advanced Application Programming Guide
and the ISQL Reference Manual for ALLBASE/SQL and IMAGE/SQL respectively for related
documentation.