Accueil Technologie Redondance des données

Redondance des données



Définition

Dataredundancywillhindertheintegrityofthedatainthedatabase, andwillalsocauseawasteofstoragespace.Toreducedataredundancyasmuchaspossibleisoneofthemaingoalsofdatabasedesign.Oneofthemainideasofthenormalizationtheoryofrelationalmodel (hereinafterreferredtoasNFtheory) istheprincipleofleastredundancy, thatis, thestandardizedrelationalmodelshouldhavetheleastredundancyinacertainsense.However, NFtheoryhasnostandardconceptavailable.Accordingtotheprincipleofequivalence, theremaybeseveralredundantdefinitionsunderdifferentpremisessuchasuniversalrelationassumptionornot.

comparaison en anglais

redondancede;redondance;redondant;degré de redondance;

explication

1, referstoaspecialemotionininterpersonalcommunicationThewayofexpressionistoconveysincereaffectionwithseeminglyredundantandirrelevantnonsense, andcausetheinteractionandreturnofemotions.Whenrelativesandfriendsmeetindailylife, knowingthattheyhaveeaten, theystillkindlyask: "Haveyoueaten?" Whentheirchildrengoout, parentswillrepeatedlywarn: "Becarefulwhencrossingthestreet" Thesebehaviorsaremanifestationsofredundancy.Duetothenarrowingofthescopeofactivitiesandtheincreaseofpsychologicalloneliness, theelderlyespeciallyhopethatacaringpersonwillnagwiththem, son ...

Cet article provient du réseau, ne représente pas la position de cette station. Veuillez indiquer l'origine de la réimpression
HAUT