ucrpq_minimization_problem (797B)
1 # UCRPQ minimization problem 2 3 [Decision_problem] defined in [morvan2025homomorphism], p91: 4 - Input: a [UCRPQ] Q and integer k 5 - Output: is there a [query_equivalent] [UCRPQ] with at most k [atoms] which is equivalent to Q 6 7 For [CRPQs], the problem is [EXPSPACE_hard] ([morvan2025homomorphism], Theorem IV.5.2) and in [2EXPSPACE] ([CRPQ_minimization_upper_bound], [morvan2025homomorphism], Theorem IV.3.1) 8 9 For [UCRPQs], the problem is [EXPSPACE_complete] ([morvan2025homomorphism], Corollary IV.4.7) 10 11 Different from [CRPQ_minimization] in the sense that there are [minimal_CRPQs] that admit a [query_equivalent] [UCRPQ] whose constituent [CRPQs] have fewer [atoms], cf [morvan2025homomorphism] Proposition IV.4.1 12 13 Up: [crpq_minimization], [decision_problem] 14 15 See also: [CRPQ_minimization_problem]