Moving To PostgreSQL (Part 1)

Goodbye Oracle, hello PostgreSQL!  I’ve decided to get out of the Oracle business and move our Enterprise Geodatabase to PostgreSQL.  I’m tired of giving Oracle lots of money each year.  PostgreSQL is open source and it is very mature.  Though we do not have a dedicated DBA here that knows PostgreSQL, they can learn!  And so can I.  Besides, ESRI supports it and if something goes wrong, I can get them on the red hotline phone!

Over the past few years, I have been testing PostgreSQL on Windows by installing it with our ArcGIS Server installations and using it to store GIS data used in our map and feature services.  I have had only one issue and it was a speed problem when selecting over 10,000 polygons in ArcMap.  ESRI confirmed it was a bug.  I believe that problem has gone away, so now is a good time to move to PostgreSQL.  But just to be sure, we will be running both Oracle and PostgreSQL in parallel for a few months.

NOTE: To be able to install an Enterprise Geodatabase in PostgreSQL, you must be running ArcGIS Server (enterprise addition) somewhere.  You need the keycodes file that was created with it to authorize the geodatabase.  You will also need the st_geometry.so file that was created when you installed ArcGIS Desktop 10.6.  More on that later.  Continue reading

Avalanche Forecasts Using GIS

SoCal does not experience avalanches very often.  Since 1950, at least 64 people have died in avalanches in California with 9 of those in SoCal, according to this article.

Snow avalanches can cause a significant loss of life. As a naturally occurring disaster they are unique in nature, usually being highly localized events, and often in remote areas. Their victims are often voluntarily at risk for recreation purposes and become the trigger of their own avalanche.

Avalanche forecasting seeks to safeguard recreationists in winter mountain environments using risk based decision making.  Avalanche experts interpret the spatial and temporal distribution of hazards and abstractly present these in the form of a forecast.  Recreationists can then use them for planning excursions into avalanche prone terrain and avoid high risk slopes that pose a hazard.

Check out this article on how Scotland looked at using GIS to make cartographic visualizations of predicted avalanche danger areas.

avalanches