Structured Query Language ==>
SQL
<language, database, standard> /S Q L/ An industry-standard language for
creating, updating and, querying relational database management systems.
SQL was developed by IBM in the 1970s for use in System R. It is the de facto
standard as well as being an ISO and ANSI standard. It is often embedded in
general purpose programming languages.
The first SQL standard, in 1986, provided basic language constructs for defining
and manipulating tables of data; a revision in 1989 added language extensions
for referential integrity and generalised integrity constraints. Another
revision in 1992 provided facilities for schema manipulation and data
administration, as well as substantial enhancements for data definition and data
manipulation.
Development is currently underway to enhance SQL into a computationally complete
language for the definition and management of persistent, complex objects. This
includes: generalisation and specialisation hierarchies, multiple inheritance,
user defined data types, triggers and assertions, support for knowledge based
systems, recursive query expressions, and additional data administration tools.
It also includes the specification of abstract data types (ADTs), object
identifiers, methods, inheritance, polymorphism, encapsulation, and all of the
other facilities normally associated with object data management.
The emerging SQL3 standard is expected to be complete in 1998.
According to Allen G. Taylor, SQL does _not_ stand for "Structured Query
Language". That, like "SEQUEL" (and its pronunciation /see'kw*l/), was just
another unofficial name for a precursor of SQL. However, the IBM SQL Reference
manual for DB2 and Craig Mullins's "DB2 Developer's Guide" say SQL _does_ stand
for "Structured Query Language".
SQL Standards.
An SQL parser is described in "Lex & Yacc", by Levine, Mason & Brown
published by O'Reilly.
The 1995 SQL Reunion: People, Projects, and Politics.
["A Guide to the SQL Standard", C.J. Date, A-W 1987].
["SQL for Dummies", Allen G. Taylor, IDG Books Worldwide].
(2005-11-17)
Nearby terms:
\sqcap « \sqcup « SQE « SQL » SQL2 » SQL3 »
SQL Access Group
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