A DBA must run a one-off DELETE to remove duplicate application records on the production database. What is the safest way to proceed?
Un administrateur de base de données doit exécuter un DELETE ponctuel pour supprimer des candidatures en double sur la base de production. Quelle est la façon la plus sûre de procéder ?
Answers
ARun it quickly at the busiest time so users can report problems straight awayL'exécuter rapidement à l'heure de pointe pour que les utilisateurs signalent aussitôt les problèmes
BRun it without a WHERE clause to be sure all duplicates are caughtL'exécuter sans clause WHERE pour être sûr d'attraper tous les doublons
CDisable all constraints firstDésactiver d'abord toutes les contraintes
DCheck rows with SELECT, back up, run in a transaction and verify before COMMITVérifier les lignes avec SELECT, sauvegarder, exécuter dans une transaction et contrôler avant le COMMIT
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