Geocoding addresses with the MMQGIS plugin within QGIS

I have been given a spreadsheet of geotechnical reports (thousands of records) that I want to plot the location of in GIS, but unfortunately the list does not have coordinates! However, many of the records have street addresses that potentially are able to be geocoded. While geocoding has some pitfuls it should at least create approximate coordinates as a starting point and batch processing could save a lot of time.

In looking through various options for batch conversion, I stumbled across the MMGIS  plugin. After a little experimentation I managed to get a reasonable result. While there is a help file available, there are a couple of steps that I am documenting more fully, for my benefit and anyone else that happens to read this blog. My explanation below applies to an address format that works in Australia. 

While it does not appear that all the attributes of the table can be loaded into the file required for processing, a unique identifier field can be added (not documented) that will allow a later table join.

The csv file format must have headers such as ID, Address, City, State, Country

An example (fictional) record to follow the header could be: 

2485, 56 Mercey Street, Hobart, Tasmania, Australia

Unfortunately the data I have been provided does not match the format exactly but the geocoding service appears to be pretty clever. For example, I entered suburb names instead of cities and I placed the post code into the address field to assist the process. This seemed to work quite well. 

There are several geocoding services available (as options in the dialogue) but I found the ESRI geocoding service worked best out of the options chosen. The API address is contained in the documentation of the plugin and this needs to be placed in the URL column when the dialogue box is opened: 

https://geocode.arcgis.com/arcgis/rest/services/World/GeocodeServer/findAddressCandidates


The output file is in WGS84 lat lon format, but this is easy to convert to a projected CRS as a subsequent step in QGIS.


I hope this helps. Many thanks to the creator of MMQGIS, Michael Minn (http://michaelminn.com), for making this tool available. 

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