This 3-part mini-course is my attempt to explain the basic concepts of working with PostGIS data from within the Leaflet.js mapping API. Technically this is not Leaflet programming. In this scenario Leaflet.js simply becomes the canvas on which your geospatial data is displayed on a web map. All of the interaction with the geospatial data occur through very common and standard methods of working with enterprise level databases, but with a geospatial twist. Continue reading “Working with PostGIS data from within Leaflet.js (or any other client side mapping API)”
In these two videos I discuss performance considerations when choosing a hosting service for your PostGIS database, how to determine if you should invest in higher download speeds on the client side or better performance on the server side, and strategies for mitigating slow response times. Continue reading “Deploying a PostGIS Database Parts 5 and 6 – Performance considerations”
In this video I show how to deploy your PostGIS database to a second remote server option, the AcuGIS Cloud. In general my perception is that getting started with AcuGIS was much easier for general GIS use than A2 hosting. They focus on GIS and they know GIS. Installing PostGIS was a breeze, they have the latest versions of both PostgreSQL and PostGIS available, they have all the extensions for PostGIS, and they have shp2pgsql and raster2pgsql available right in their control panel which simplifies loading your data. Continue reading “Deploying a PostGIS database Part 4 – The AcuGIS Cloud”
In the previous 2 videos we signed up for a web hosting service and deployed a PostGIS database to it. In this video we will move the database that we have been working with on our localhost instance to the server so that it can be accessed by other clients. Continue reading “Deploying a PostGIS database Part 3 – Moving your database to the server”
This video goes through the process of signing up for a web hosting service with A2 hosting. You can literally have an instance of PostGIS up and running in half an hour for under $5/month that can be accessed from your own web map or from other clients such as QGIS.
What makes A2 Hosting so good for GIS applications is that they offer PostgreSQL databases in their standard cPanel package which means that you can easily install and use PostGIS. Most web hosting services only offer MySQL although you may be able to have them install PostgreSQL for you. Continue reading “Deploying a PostGIS database Part 2 – Web hosting service”
Learning to use PostGIS deployed on your local computer is very simple. The real power of a spatial database, however, is setting it up on a server so that it can be accessed by multiple clients simultaneously. This is a little bit more complicated. Continue reading “Deploying a PostGIS database Part 1 – Background”
For many years I had been hearing about spatial databases. I knew that some of the frustrating issues I was dealing with as the GIS specialist for small environmental consulting companies could be addressed with the technology. But consulting is all about billable hours and its really hard to convince your boss to give you the unbillable time needed to figure it all out. And its really hard and probably unethical to expect a client to let you figure it all out on their dime. So until a few years ago I kept chugging away with single-user file-based data storage and wasted an enormous amount of time managing data and people to prevent conflicts that could have easily been prevented with a spatial database. Continue reading “Getting started with PostGIS”
I have nothing against ESRI, they have been innovators in the geospatial software world from the beginning. I got into GIS from a natural resources background and I know that they have supported the conservation community for decades through their conservation grants program and many other ways. Jack Dangermond’s recent donation of $165 million to the Nature Conservancy to purchase one of the last large undeveloped parcels of southern California coastline stirred my heart and made me well up in tears with pride in the GIS community. I am not opposed to companies selling GIS software for profit. I believe in capitalism. I believe that entrepreneurs should be rewarded financially for producing high quality products at a fair price. Continue reading “The case for open-source GIS”
All of my courses are available on the Udemy platform. This means that
- They are self-paced. Start when you want and take as long as you want to finish
- They are available 24-7 on-line
- They can be downloaded to a mobile device and watched off-line
- They have life-time access
- The price is $20 each for readers of this blog.
All of my courses use open source software and simple, standard methods that have stood the test of time. They can be implemented without spending anything on licensing, subscriptions, or per-user fees. Many of the concepts you will learn can be applied to commercial software as well but I think you will be impressed with the power and ease of the open source ecosystem, especially for multi-user geospatial applications.
Web Programming courses for Geospatial
- Introduction to web programming for GIS applications – This course is the foundation on which all my other web programming courses are based on. Its purpose is to provide the background necessary to understand the big picture of how various technologies, from basic HTML to PostGIS databases, work together to form a web GIS application. This course is intended to be watched with the intention of understanding the big picture. It is not intended to be followed along step by step, although several people have been able to do so. (13 hours) AVAILABLE NOW. *** BESTSELLER ***
- Display and analyze your GIS data on the web with Leaflet – This course builds on the first half of the previous course and provides much more detail on the Leaflet.js API and the Turf.js API for spatial analysis. Students are expected to follow along on their own computers and build a web map from start to finish. This course only covers client-side technologies, i.e. displaying and analyzing static data. It does not cover creating and/or editing data via the web although that subject is introduced in the introductory course. (13 hours) AVAILABLE NOW. *** BESTSELLER ***
- Mobile GIS and mapping applications with Leaflet – This course builds on the previous two to cover issues specific to mobile devices, This includes dealing with small screens, touch screens, accessing the devices sensors, and working off-line. (4 hours) AVAILABLE NOW $15 until August 31
- PHP registration, login, and content management system – One of the most frequent questions that I get is “How do I control access to my web pages and content?”. This course attempts to answer that question by providing step-by-step instructions for developing a user registration, login, and content management system that you can use for your own projects as-is or modify to suit your purpose. (9 hours) AVAILABLE NOW
- Server based web gis applications with Leaflet and PostGIS – This course will build on the introductory course to provide much more detail on integrating Leaflet web maps with a spatial database. It covers server-side programming with PHP, AJAX, and SQL. This is necessary for applications where the user is allowed to create and/or edit data via the web. Although I use Leaflet and postGIS as examples in this book the concepts are easily transferable to any client side web mapping API that can display GeoJSON and any server-side database. (16.5 hours) AVAILABLE NOW.
- Mobile data collection applications with Leaflet and PostGIS – This course will build on the previous course and show how to develop applications for collecting data in the field using the devices GPS sensor. AVAILABLE NOW
QGIS and PostGIS courses
- QGIS 3.0 for GIS Professionals – This course is projected to be available concurrently with the release of QGIS 3.0 It will provide an overview of QGIS specifically for GIS users who are already trained in the use of commercial GIS software. Over 10 hours of content. AVAILABLE NOW!!! *** BESTSELLER ***
- Spatial databases with QGIS and PostGIS – This course is intended to provide an introduction in using spatial databases (based on PostGIS) for storing and analyzing geospatial data through SQL commands Over 10 hours of content. Available NOW!!! *** HIGHEST RATED ***
- Survey of python for GIS applications – This course will provide a review of the python language and the python ecosystem for data analysis and geospatial applications. This course teaches PYTHON, not a particular library such as ArcPy or PyQGIS, but I think you will be impressed with what you can do with pure python not tied to a particular desktop GIS software and if you do decide you really want to work with ArcPy or PyQGIS you will have a strong basis for learning those libraries. Available Now
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In a recent post, I attempted to answer the question What can a spatial database do for you? That post was a broad overview of the advantages of storing your geospatial data in a spatial database. This post follows up with more specific information on how to get started and step by step instructions on using one type, SpatiaLite, with the popular open source GIS software QGIS. Continue reading “Quick start to spatial databases with QGIS and SpatiaLite”