{"product_id":"exploiting-constraints-in-query-processing-von-junhu-wang","title":"Exploiting Constraints in Query Processing","description":"\u003cp\u003eThis book focuses on the optimization of general conjunctive queries (GCQ) using integrity constraints and in the presence of materialized  views. A GCQ is a conjunctive query with arbitrary  built-in predicates. The integrity constraints we  consider are disjunctive constrained tuple- generating dependencies (DCTGDs)which include many  traditional integrity constraints such as functional  dependencies, inclusion dependencies, and  constrained tuple-generating dependencies.  We first present an improved method for testing  general conjunctive query containment using  relevance mappings. We then present a method for  testing general conjunctive query containment in the  presence of DCTGDs.  Our method generalizes and improves previous algorithms for the semantic  containment problem of conjunctive queries.  When materialized views exist, we study the problem  of rewriting a union of general conjunctive queries  using the view relations under the  open world  assumption and present a general approach for such  problems. Our approach can rewrite unions of general  conjunctive queries when both the query and the  views involve built-in predicates.\u003c\/p\u003e\u003cdiv class=\"aw-variant-hidden-subtitle-div\" id=\"aw-variant-subtitle-9783838331508\"\u003e\u003ch3\u003eQuery transformation using interity constraints and views\u003c\/h3\u003e\u003c\/div\u003e","brand":"Autorenwelt Shop","offers":[{"title":"Softcover - 9783838331508","offer_id":39498948903005,"sku":"9783838331508","price":79.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0940\/0622\/files\/4f25a201-0299-4374-b094-de42d555d62d.jpg?v=1772779898","url":"https:\/\/shop.autorenwelt.de\/products\/exploiting-constraints-in-query-processing-von-junhu-wang","provider":"Autorenwelt Shop","version":"1.0","type":"link"}