relational model
relational model A
data model that views information in a database as a collection of distinctly named tables. Each table has a specified set of named columns, each column name (also called an
attribute) being distinct within a particular table, but not necessarily between tables. The entries within a particular column of a table must be atomic (that is, single data items) and all of the same type. The logical
records held in a relational database are viewed as rows in these tables. Each logical record is thus constrained to contain only a set of elementary data items each of a prespecified type. The model is, in consequence, also known as the
flat file model.
The model, first proposed by Codd in 1969 and used exclusively in the context of
database management systems, takes its name from an analogy that can be drawn between a table as described and the mathematical concept of a
relation. In this analogy table corresponds to relation, row (in a table) to tuple (of a relation), and the column names (of the table) to the domain ordering (in the relation). Using this analogy Codd developed various sets of operations on which languages for the manipulation of such tables might be based and from which the now widely used data sublanguage
SQL is derived.
In spite of its name, which can be a source of confusion, the model makes no provision for maintaining relationships between rows in different tables and the only constraint on the rows within a particular table is that no two rows are identical. Each row, from the viewpoint of the model, is thus an independent entity. It can only be related to other rows by correspondences between contained data items, which is a matter for the user.
See also
normal forms,
foreign key,
ERA model.
Cite this article
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Samurai Bows Before Its Star; Tom Cruise blends history with Bushido honor code in epic drama.
Newspaper article from: Coast weekly; 12/10/2003; ; 700+ words
; ...Nathan Algren for Ed Zwick's The Last Samurai. After being hired to train a regiment...Emperor of Japan, Algren is captured by Samurai and tutored to live as they do. Algren...inner nature is more in harmony with the Samurai than his previous path as a mercenary...
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'Samurai Chess' for iPhone/iPod Touch is Released at the APP Store by CONIT Co., Ltd.
PR Newswire; 12/11/2008; 700+ words
; ...game faithfully depicts the world of the Samurai in the Japanese civil war era. A network...Ltd. announced today the release of "Samurai Chess" for iPhone/iPod at the APP Store. "Samurai Chess" is basically an orthodox chess game...
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 "Chicago Tribune (Chicago, IL)")
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Samurai series' swords slashing at Music Box.
Newspaper article from: Chicago Tribune (Chicago, IL); 3/3/2006; 700+ words
; ...movie aficionado than a good Japanese samurai movie, especially the ones made during...and even tragedy. On the Music Box "Samurai Cinema!" series, starting Friday...inarguable masterpieces (Kurosawa's "Seven Samurai," "Yojimbo" and "The Hidden Fortress...
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 "The Mail on Sunday (London, England)")
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SAMURAI KNIGHT FEVER; Will The Last Samurai, in which Tom Cruise plays an American who becomes a samurai knight, deliver his first Oscar? Fred Schruers spoke exclusively to the film's makers and Cruise himself.
Newspaper article from: The Mail on Sunday (London, England); 12/28/2003; 700+ words
; ...office prospects. In the case of The Last Samurai, that platform is the story of a disillusioned...involvement of Cruise, who is one of The Last Samurai's producers, as well as its star...authenticity. The spadework for The Last Samurai began, says producer Scott Kroopf...
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'Samurai' remains a great among the greats
Newspaper article from: Chicago Sun-Times; 11/8/2002; ; 700+ words
; ...Roger Ebert's 2001 essay on "The Seven Samurai," which can be found in his book, The...Books). Akira Kurosawa's "The Seven Samurai" (1954) is not only a great film in...and caper movies. Since Kurosawa's samurai adventure "Yojimbo" (1960) was remade...
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'Samurai' a good film maybe, but good history unlikely
Newspaper article from: Oakland Tribune; 11/27/2003; ; 700+ words
; WHEN the film "The Last Samurai" (Warner Bros.) opens Dec. 5 it...Considering the popular notion of what the Samurai were, probably not, according to...Conlan extensively has researched the Samurai and warfare in 14th- century Japan...
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Samurai Sam's Teriyaki Grill Gets a New Look; Tempe Franchisee is First in the United States to Unveil Company's New Decor Package.
Business Wire; 12/16/2005; 700+ words
; ...Here in the Valley, Scottsdale-based Samurai Sam's Teriyaki Grill is one quick...board and facility package at the Tempe Samurai Sam's restaurant located at 920 E...service restaurant concepts, including Samurai Sam's, partnered with design firm M3...
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`Samurai' cuts to warrior's soul.(Arts and Lifestyle)
Newspaper article from: The Boston Herald; 6/4/2004; ; 700+ words
; ...Byline: JAMES VERNIERE "The Twilight Samurai." Not rated. In Japanese with English...s generic spectacles, "The Twilight Samurai" is the Japanese "Shane," an intensely...Japanese veteran Yoji Yamada, "The Twilight Samurai" is set in 19th century Edo period Japan...
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The Samurai superintendent.(Executive Perspective)
Magazine article from: School Administrator; 9/1/2004; ; 700+ words
; For more than 1,000 years the Samurai warrior in Japan carried a tradition. While our Western notion of the Samurai conjures up a fierce fighter wielding...in battle, the real tradition of the Samurai is much more nuanced and appropriate...
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Samurai fights his way into Western pop culture.(Knight Ridder Newspapers)
Newspaper article from: Knight Ridder/Tribune News Service; 12/8/2003; ; 700+ words
; Byline: Pat Berman "The Last Samurai" is the latest entry into the East...and popular culture. But onscreen, the samurai, the cowboy, the soldier of fortune...in the movies. The reality is, "The samurai ethic is very group oriented," says...
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Samurai
Book article from: Fashion, Costume, and Culture: Clothing, Headwear, Body Decorations, and Footwear through the Ages
SAMURAI Samurai (SAM-er-eye) were Japanese warriors who were revered for their skills...warriors, but also for their distinct influence on Japanese fashion. Samurai first appeared in Japan as early as the eighth century c.e., but they...
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samurai
Book article from: The Columbia Encyclopedia, Sixth Edition
samurai , knights of feudal Japan, retainers of...was consolidated in the Tokugawa period. Samurai were privileged to wear two swords, and...loyalty to their overlords (see bushido ). Samurai were the dominant group in Japan, and...
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Shichinin No Samurai
Dictionary entry from: International Dictionary of Films and Filmmakers
SHICHININ NO SAMURAI (The Seven Samurai) Japan, 1954 Director: Akira Kurosawa Production: Toho Productions...archery masters: Ienori Kaneko and Shigeru Endo. Cast: The Samurai: Takashi Shimura (Kambei, the leader ); Toshiro Mifune...
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The Seven Samurai
Dictionary entry from: International Dictionary of Films and Filmmakers
THE SEVEN SAMURAI See SHICHININ NO SAMURAI
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Samurai bond
Book article from: A Dictionary of Business and Management
Samurai bond A bond issued in Japan by a foreign institution. It is denominated in yen and can be bought by non-residents of Japan.
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