Join: Another Form of Composition
Other forms of composition of relations, which apply to general n-place relations instead of binary relations, are found in the join operation of relational algebra. The usual composition of two binary relations as defined here can be obtained by taking their join, leading to a ternary relation, followed by a projection that removes the middle component.
Read more about this topic: Composition Of Relations
Famous quotes containing the words form and/or composition:
“Although Samuel had a depraved imagination—perhaps even because of this—love, for him, was less a matter of the senses than of the intellect. It was, above all, admiration and appetite for beauty; he considered reproduction a flaw of love, and pregnancy a form of insanity. He wrote on one occasion: “Angels are hermaphrodite and sterile.””
—Charles Baudelaire (1821–1867)
“There is singularly nothing that makes a difference a difference in beginning and in the middle and in ending except that each generation has something different at which they are all looking. By this I mean so simply that anybody knows it that composition is the difference which makes each and all of them then different from other generations and this is what makes everything different otherwise they are all alike and everybody knows it because everybody says it.”
—Gertrude Stein (1874–1946)