December 2014
Intermediate to advanced
852 pages
17h 57m
English
Content preview from Joe Celko's SQL for Smarties, 5th Edition
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Chapter 31
Partitioning and Aggregating Data in Queries
Abstract
This section is concerned with how to break the data in SQL into meaningful subsets that can then be presented to the user or passed along for further reduction. This is not the same as physical partitioning which moves data to slower storage administrative reasons.
Keywords
Subsets
Partition
Covering
Ranges
Soundex function
NTILE()
This chapter is concerned with how to break the data in SQL into meaningful subsets that can then be presented to the user or passed along for further reduction.
31.1 Coverings and Partitions
We need to define some basic set operations. A covering is a collection of subsets, drawn from a set, whose union is the original set. A partition is a covering ...
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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.