June 2010
Intermediate to advanced
328 pages
7h 51m
English
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How to Recognize the Antipattern
If you find yourself or another member of your team describing issues like the following, it could be because of improper handling of nulls:
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“How do I find rows where no value has been set in the assigned_to (or other) column?”
You can’t use the equality operator for null. We’ll see how to use the IS NULL predicate later in this chapter.
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“The full names of some users appear blank in the application presentation, but I can see them in the database.”
The problem might be that you’re concatenating strings with null, which produces null.
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“The report of total hours spent working on this project includes only a few of the bugs that we completed! Only those for which we assigned a priority are included.” ...
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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.