Solving Equations in the Relational Algebra
نویسندگان
چکیده
منابع مشابه
Solving Equations in the Relational Algebra
Enumerating all solutions of a relational algebra equation is a natural and powerful operation which, when added as a query language primitive to the nested relational algebra, yields a query language for nested relational databases, equivalent to the well-known powerset algebra. We study sparse equations, which are equations with at most polynomially many solutions. We look at their complexity...
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ژورنال
عنوان ژورنال: SIAM Journal on Computing
سال: 2004
ISSN: 0097-5397,1095-7111
DOI: 10.1137/s0097539701390859