July 2010
Intermediate to advanced
840 pages
16h 33m
English
Content preview from Joe Celko's SQL for Smarties, 3rd Edition
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Chapter 27. Subsets
I AM DEFINING SUBSET operations as queries, which extract a particular subset from a given set, as opposed to set operations, which work among sets. The obvious way to extract a subset from a table is just to use a WHERE clause, which will pull out the rows that meet that criterion. But not all the subsets we want are easily defined by such a simple predicate. This chapter is a collection of tricks for constructing useful, but not obvious, subsets from a table.
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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.
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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.