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 7
Quiz
| 1: | In the section “Nesting Subqueries,” the sample subquery returned several values:LE SHOPPE BIKE SPEC LE SHOPPE BIKE SPEC JACKS BIKE Some of these are duplicates. Why aren't these duplicates in the final result set? |
| A1: | The result set has no duplicates because the query that called this subquery
SELECT ALL C.NAME, C.ADDRESS, C.STATE,C.ZIP FROM CUSTOMER C WHERE C.NAME IN returned only the rows where NAME was in the list examined by the statement IN. Don't confuse this simple IN with the more complex JOIN. |
| 2: | Are the following statements true or false?
|
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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.