Enumeration of Minimal Hitting Sets Parameterized by Treewidth

Enumerating the minimal hitting sets of a hypergraph is a problem which arises in many data management applications that include constraint mining, discovering unique column combinations, and enumerating database repairs. Previously, Eiter et al. [22] showed that the minimal hitting sets of an n-vertex hypergraph, with treewidth w, can be enumerated with delay O^∗(n^w) (ignoring polynomial factors), with space requirements that scale with the output size. We improve this to fixed-parameter-linear delay, following an FPT preprocessing phase. The memory consumption of our algorithm is exponential with respect to the treewidth of the hypergraph.