The closed world assumption

"The presentation is divided into four modules. Module I lays some important groundwork, discussing predicates and constraints in particular and stressing the importance of database consistency. Module II considers consistency in more detail and then discusses a simple example in depth, buildin...

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Bibliographic Details
Other Authors: Date, C. J., on-screen presenter (onscreen presenter)
Format: Online Video
Language:Inglés
Published: [Place of publication not identified] : O'Reilly Media 2014.
Edition:1st edition
Subjects:
See on Biblioteca Universitat Ramon Llull:https://discovery.url.edu/permalink/34CSUC_URL/1im36ta/alma991009629718506719
Description
Summary:"The presentation is divided into four modules. Module I lays some important groundwork, discussing predicates and constraints in particular and stressing the importance of database consistency. Module II considers consistency in more detail and then discusses a simple example in depth, building to the conclusion that the OWA and the relational model are fundamentally and irrevocably at odds with each other (which is why in practice we always adopt the CWA). Module III then goes into more depth on predicates and shows how to get "don't know" answers out of the database (when appropriate) without any need for nulls or three-valued logic (3LV). Finally, Module IV shows how the CWA can even be used in connection with predicates involving negation or conjunction."--Resource description page.
Item Description:Title from title screen (viewed December 18, 2014)
Date of publication taken from resource description page.
Physical Description:1 online resource (1 streaming video file (1 hr., 34 min., 42 sec.)) : digital, sound, color