000 03793nam a22004935i 4500
001 978-3-031-01883-1
003 DE-He213
005 20240730163741.0
007 cr nn 008mamaa
008 220601s2011 sz | s |||| 0|eng d
020 _a9783031018831
_9978-3-031-01883-1
024 7 _a10.1007/978-3-031-01883-1
_2doi
050 4 _aTK5105.5-5105.9
072 7 _aUKN
_2bicssc
072 7 _aCOM043000
_2bisacsh
072 7 _aUKN
_2thema
082 0 4 _a004.6
_223
100 1 _aBertossi, Leopoldo.
_eauthor.
_4aut
_4http://id.loc.gov/vocabulary/relators/aut
_980367
245 1 0 _aDatabase Repairing and Consistent Query Answering
_h[electronic resource] /
_cby Leopoldo Bertossi.
250 _a1st ed. 2011.
264 1 _aCham :
_bSpringer International Publishing :
_bImprint: Springer,
_c2011.
300 _aXV, 105 p.
_bonline resource.
336 _atext
_btxt
_2rdacontent
337 _acomputer
_bc
_2rdamedia
338 _aonline resource
_bcr
_2rdacarrier
347 _atext file
_bPDF
_2rda
490 1 _aSynthesis Lectures on Data Management,
_x2153-5426
505 0 _aIntroduction -- The Notions of Repair and Consistent Answer -- Tractable CQA and Query Rewriting -- Logically Specifying Repairs -- Decision Problems in CQA: Complexity and Algorithms -- Repairs and Data Cleaning.
520 _aIntegrity constraints are semantic conditions that a database should satisfy in order to be an appropriate model of external reality. In practice, and for many reasons, a database may not satisfy those integrity constraints, and for that reason it is said to be inconsistent. However, and most likely, a large portion of the database is still semantically correct, in a sense that has to be made precise. After having provided a formal characterization of consistent data in an inconsistent database, the natural problem emerges of extracting that semantically correct data, as query answers. The consistent data in an inconsistent database is usually characterized as the data that persists across all the database instances that are consistent and minimally differ from the inconsistent instance. Those are the so-called repairs of the database. In particular, the consistent answers to a query posed to the inconsistent database are those answers that can be simultaneously obtained from all the database repairs. As expected, the notion of repair requires an adequate notion of distance that allows for the comparison of databases with respect to how much they differ from the inconsistent instance. On this basis, the minimality condition on repairs can be properly formulated. In this monograph we present and discuss these fundamental concepts, different repair semantics, algorithms for computing consistent answers to queries, and also complexity-theoretic results related to the computation of repairs and doing consistent query answering. Table of Contents: Introduction / The Notions of Repair and Consistent Answer / Tractable CQA and Query Rewriting / Logically Specifying Repairs / Decision Problems in CQA: Complexity and Algorithms / Repairs and Data Cleaning.
650 0 _aComputer networks .
_931572
650 0 _aData structures (Computer science).
_98188
650 0 _aInformation theory.
_914256
650 1 4 _aComputer Communication Networks.
_980368
650 2 4 _aData Structures and Information Theory.
_931923
710 2 _aSpringerLink (Online service)
_980369
773 0 _tSpringer Nature eBook
776 0 8 _iPrinted edition:
_z9783031007552
776 0 8 _iPrinted edition:
_z9783031030116
830 0 _aSynthesis Lectures on Data Management,
_x2153-5426
_980370
856 4 0 _uhttps://doi.org/10.1007/978-3-031-01883-1
912 _aZDB-2-SXSC
942 _cEBK
999 _c84947
_d84947