Sublanguage
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A sublanguage is a subset of a language. Sublanguages occur in natural language, computer programming language, and relational databases.
In natural language
In
In computer languages
The term sublanguage has also sometimes been used to denote a computer language that is a subset of another language. A sublanguage may be restricted syntactically (it accepts a subgrammar of the original language), and/or semantically (the set of possible outcomes for any given program is a subset of the possible outcomes in the original language).
Examples
For instance, ALGOL 68S was a subset of ALGOL 68 designed to make it possible to write a single-pass compiler for this sublanguage.
SQL (Structured Query Language) statements are classified in various ways,[5] which can be grouped into sublanguages, commonly: a data query language (DQL), a data definition language (DDL), a data control language (DCL), and a data manipulation language (DML).[6]
In relational database theory
In
- A relational system may support several languages and various modes of terminal use (for example, the fill-in-the-blanks mode). However, there must be at least one language whose statements are expressible, per some well-defined syntax, as character strings, and that is comprehensive in supporting all of the following items:
- Data definition
- View definition
- Data manipulation (interactive and by program)
- Integrity constraints
- Authorization
- Transaction boundaries (begin, commit, and rollback)
References
- ^ Harris, Zellig (1988). Language and Information. New York: Columbia University Press.
- ^ Kittredge, Richard; Lehrberger, John (1982). Sublanguage: Studies of language in restricted semantic domains. Berlin: Walter de Gruyter.
- ^ Sager, Naomi; Nhàn, Ngô Thanh (2002). "The computability of strings, transformations, and sublanguage". In Nevin, Bruce E; Johnson, Stephen M (eds.). The Legacy of Zellig Harris (PDF). Amsterdam/Philadelphia: John Benjamins. pp. 79–120. Retrieved 22 September 2020.
- . Retrieved 22 September 2020.
- ^ SQL-92, 4.22 SQL-statements, 4.22.1 Classes of SQL-statements "There are at least five ways of classifying SQL-statements:", 4.22.2, SQL statements classified by function "The following are the main classes of SQL-statements:"; SQL:2003 4.11 SQL-statements, and later revisions.
- ISBN 978-1-29119951-2.
- ^ Codd, E (October 14, 1985). "Computer World". Is Your DBMS Really Relational?.
- ^ Codd, E (October 21, 1985). "Computer World". Does Your DBMS Run By The Rules?.