Relational Algebra as non-Distributive Lattice
نویسنده
چکیده
We reduce the set of classic relational algebra operators to two binary operations: natural join and generalized union. We further demonstrate that this set of operators is relationally complete and honors lattice axioms.
منابع مشابه
Homomorphisms of relational systems and the corresponding groupoids
A nearlattice is a meet semilattice A in which every initial segment Ap := {x : x ≤ p} happens to be a join semilattice (hence, a lattice) with respect to the natural ordering of A. If all lattices Ap are distributive, the nearlattice itself is said to be distributive. It is known that a distributive nearlattice can be represented as a nearlattice of sets. We call an algebra (A,∧,∨) of type (2,...
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عنوان ژورنال:
- CoRR
دوره abs/cs/0501053 شماره
صفحات -
تاریخ انتشار 2005