June 2017
Beginner
428 pages
10h 2m
English
Content preview from Practical GIS
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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.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.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.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.
Optimizing queries
We already used some techniques to speed up queries, although we have a lot more possibilities in tuning queries for faster results. To get the most out of our database, let's see how queries work. First of all, in RDBMS jargon, tables, views, and other similar data structures are called relations. Relation data is stored in files consisting of static-sized blocks (pages). In PostgreSQL, each page takes 8 KB of disk space by default. These pages contain rows (also called tuples). A page can hold multiple tuples, but a tuple cannot span multiple pages. These tuples can be stored quite randomly through different pages; therefore, PostgreSQL has to scan through every page if we do not optimize the given relation. One of 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.