SAP SE
SELECTIVITY ESTIMATION OF CONJUNCTIVE PREDICATES

Abstract:

A system includes determination of a query comprising z predicates, determination of known selectivities of each of a set of conjuncts of the z predicates, and estimation of selectivities of all conjuncts of the z predicates based on the known selectivities and a recursive determination of Cx, where x represents selectivities of all complete conjuncts of the z predicates and C is a complete design matrix complete design matrix (c.sub.i,j)=1 if ij, else 0, having indices [0, 2.sup.z-1].