April 2024
Intermediate to advanced
800 pages
18h 34m
English
Content preview from SQL All-in-One For Dummies, 4th Edition
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Chapter 4
Creating a Database with SQL
IN THIS CHAPTER
Building tables
Setting constraints
Establishing relationships between tables
Altering table structure
Deleting tables
As I stated way back in Book 1, Chapter 5, SQL is functionally divided into three components: the Data Definition Language (DDL), the Data Manipulation Language (DML), and the Data Control Language (DCL). The DDL consists of three statements: CREATE, ALTER, and DROP. You can use these statements to create database objects (such as tables), change the structure of an existing object, or delete an object. After you have designed a database, the first step in bringing it into reality is to build a table with the help of the DDL. After you have built the tables, the next step is to fill them with data. That’s the job of the DML. As for the DCL, you call on it to help you preserve data integrity. In this chapter, I discuss the functions of the DDL. The aspects of the DML that were not covered in Book 1 — namely queries ...
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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.