October 2020
Intermediate to advanced
368 pages
9h 1m
German
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
9
Integrität und Trigger
Die Korrektheit eines Datenbestands ist in vielen Szenarien unabdingbar. Diese Korrektheit kann auf unterschiedlichste Art und Weise gefährdet sein, etwa durch unbeabsichtigte oder beabsichtigte Fehleingaben oder durch technische Probleme. Dieser Abschnitt beschäftigt sich mit einigen Funktionalitäten von DBMS, die hier korrigierend eingreifen bzw. präventiv vorbeugen können.
Die Korrektheit eines Datenbestands wird als dessen Integrität bezeichnet. Wir unterscheiden zwei Arten der Integrität:
• Die semantische Integrität besagt, dass ein korrekter (konsistenter) Datenbankzustand nach Ende einer sogenannten Transaktion (s.u.) vorliegt. Konsistenz bezieht sich dabei auf die Bedeutung (Semantik) der Daten: So ist eine negative ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.