MySQL 8.0.11 comes with a catalog of 5108 spatial reference system (SRS) definitions. In a previous post, we covered the definitions of geographic SRSs. In this post we’ll go into the details of projected SRSs. (If you haven’t done so already, I suggest you read the previous post first.)
Projected SRSs are flat, Cartesian coordinate systems created by projecting points on (an oblate spheroidal model of) Earth onto a flat surface.…
MySQL 8.0.11 comes with a catalog of 5108 spatial reference system (SRS) definitions, and 479 of these are geographic. We usually just refer to them by SRID, but in this blog post we’ll dive into the details and try to understand the definition itself.…
One of the big features of MySQL 8.0 is geography support. MySQL now has a catalog of spatial reference systems (SRSs), of which almost 500 are geographic. Most functions also support geographic computations. What about indexes?
MySQL 8.0 comes with InnoDB spatial indexes for geographic data.…
MySQL 8.0 has many new GIS features, including a catalog of spatial reference systems (SRSs) and support for geographic (latitude-longitude) computations.
In a Cartesian SRS, it doesn’t really matter which coordinate is on which axis. The axes are orthogonal and the units are the same on both axes, so if a user consistently puts the X value in the Y coordinate and the Y value in the X coordinate, it doesn’t affect computations (in the functions MySQL currently supports).…
MySQL 8.0.11 comes with a catalog of 5108 spatial reference systems (SRSs): 4628 projections (flat maps), 479 geographic (ellipsoidal) representations of Earth, and one Cartesian all-purpose abstract plane (SRID 0).
Projections
Projected SRSs are Cartesian planes, just like SRID 0.…
MySQL 8.0 brings a lot of new spatial features. The main feature is the support for multiple spatial reference systems (SRSs).
Spatial reference systems is not a new concept in MySQL, but 8.0 is the first version where it affects computations, and it’s the first version where users actually have to think about it.…
In MySQL 5.7.6 we’ve done some major spring cleaning within the GIS function namespace. We have deprecated 66 function names and added 13 new aliases. Please see the release notes for a complete list of all the changes. But why have we done this, and what impact does this have for you?
Standardization
GIS is a growing area, and to keep MySQL up to speed we have made the GIS namespace more SQL/MM compliant. …
[Read more]In recent years, GeoJSON has become a popular data format for exchanging GIS data due to several factors. The primary factors being that it’s easy to read, and it’s simple and lightweight. In 5.7.5, we added support for parsing and generating GeoJSON documents via two new functions: ST_GeomFromGeoJson() and ST_AsGeoJson(). These functions makes it easy to connect MySQL with other GeoJSON enabled software and services, such as the Google Maps Javascript API.
Since GeoJSON is a JSON format, we needed a library to parse and write JSON documents. After evaluating several candidates, we ended up with rapidjson due to its features, speed, and compatible license.
The new …
[Read more]In MySQL 5.7.5, we introduced new functions for encoding and decoding Geohash data. Geohash is a system for encoding and decoding longitude and latitude coordinates in the WGS 84 coordinate system, into a text string. In this blog post we will take a brief look at a simple example to explain just how geohash works.
Where on earth is “u5r2vty0″?
Imagine you get a email from your friend, telling you that there is free food at “u5r2vty0″. But where on earth is “u5r2vty0″?
The first step in converting from “u5r2vty0″ to latitude and longitude data, is decoding the text string into its binary representation. Geohash uses base32 characters, and you can find the character mapping on …
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