Was bedeutet der folgende Ausdruck:
ON DELETE SET NULL / ON UPDATE SET NULL
ON DELETE SET NULL / ON UPDATE SET NULL
Wenn in der Master-Tabelle ein Wert gelöscht/verändert wird, werden die Referenzen in der Detail-Tabelle auf NULL gesetzt
Tags: Datenbank, detail-tabelle, master-tabelle, NULL, ON DELETE SET NULL, ON UPDATE SET NULL, referenz, sql
Source:
Source:
Flashcard set info:
Author: Stejan
Main topic: Informatik
Topic: SQL
School / Univ.: ZbW
City: St. Gallen
Published: 04.03.2011
Tags: sql database datenbank
Card tags:
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ALL (1)
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