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. Creating Indexes on Tables to Improve Performance
Today, we talk about indexes, which provide you with a shorter route to your data. So far, you have learned how to create tables, populate tables with data, and select data from tables. Now, how can we get to data faster? Using indexes. Indexes are objects based on data in tables. Unlike views, which we discussed during the previous day, indexes do indeed require physical storage. By the end of today, you will understand the following:
How to create indexes
How to create composite indexes
What indexes do
When indexes should be used
When it is better not to use an index
An index is a way of presenting data differently than the way it appears on the disk. Special types of indexes reorder the ...
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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.