October 2002
Beginner
864 pages
18h 41m
English
Content preview from Sams Teach Yourself SQL in 21 Days, Fourth Edition
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Day 15
Quiz
| 1: | What will happen if a unique index is created on a nonunique field? |
| A1: | If there are already nonunique values in the column to be indexed, the index will not be created. If there are not nonunique values in the column to be indexed, the index will be created, but will not allow duplicate values in the indexed column. |
| 2: | Are the following statements true or false?
|
| A2: |
|
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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.