A Little Noise

Workbench announced support for a spatial view in 6.2, but examples are somewhat lacking. Just how do you get a SHP into MySQL?

Download and unpack a SHP file such as these country boundaries.

In the Workbench installation directory, you’ll find a program “ogr2ogr” that can convert .shp or GeoJSON and load it straight into MySQL.

“C:\Program Files\MySQL\MySQL Workbench 8.0\ogr2ogr.exe” -f MySQL MySQL:databaseNameHere,user=userNameHere,password=passwordHere World_Countries_Generalized.shp -nln worldmap -lco GEOMETRY_NAME=p

(It might give the error ERROR 1: PROJ: proj_identify: Cannot find proj.db which it seems can be ignored.)

Now just select rows of interest in Workbench, click the Spatial View format button, and there’s your world map.

You can run multiple selects (such as the citylot data from yesterday’s post) to overlay on top of the world map.

MySQL 5.7 came out with support for JSON, improved geometry, and virtual columns. Here’s an example showing them all playing together.

Download citylots.json.

It comes as one big object, so we’ll break it up into separate lines:
grep "^{ .type" citylots.json > properties.json

Connect to a 5.7 instance of MySQL.

CREATE TABLE citylots (id serial, j json, p geometry as (ST_GeomFromGeoJSON(j, 2)));
LOAD DATA LOCAL INFILE 'properties.json' INTO TABLE citylots (j);

A few of the rows don’t contain useful data:
DELETE FROM citylots WHERE j->'$.geometry.type' IS NULL;

In MySQL Workbench, do:
SELECT id, p FROM citylots;

Then click on Spatial View. It takes a couple of minutes for 200k rows, but there’s a map of San Francisco.

The default projection, ‘Robinson’, is designed for showing the whole world at once and so is pretty distorted for this particular data set. Mercator or Equirectangular are better choices. Fortunately, Workbench repaints the data in just a few seconds.

If you selected some other fields, you can click on the map and see the relevant data for that particular geometry.