Commenting changesets

On one of the mailing lists has been requested that mappers use the changeset comment in a more sensible way. However it has not very clearly been pointed out what information actually makes sense to put there, and I - as possibly some others - only have my own vague ideas about it.

Currently, this is:

  • information on the source (e.g. “source: survey” or “source: landsat”) unless this is put in the changeset’s source tag or source tags are added to the objects themselves
  • perhaps the focus or target of the edits (could be e.g. “correcting keepright issues”)
  • in case of changing other contributors’ work in a way that might upset them, it may be helpful to briefly state why you regard this as improvement
  • Not quite sure: is it helpful to give information on the location (country, region/city etc.) edited? This seems somewhat redundant as location information is within the data already.

Once I have gathered some feedback, I would like to add these informations on the wiki page about changesets.

I think the changeset comment should give a short summary of the changes. Mappers without local knowledge should understand it.

3 items I found helpful:

  1. Object of the change: Where and what object is it.
    This is more than just a location information.

  2. Type of the change: Adding, correcting, deleting objects or tags.

  3. Source of the information leading to the change if not tagged to the objects

Some examples how I'm trying to do this:
  • Thailand, Ubonrat Reservoir: LandSat tracing new, multipolygon, adding islands. Adding river.

  • Thailand, Khao Laem Reservoir: one multipolygon instead of six, removing tags from outer, tagging islands, adding islands.

  • Thailand, Songkhla: Enhancing Thale Sap, Thale Sap Songkhla as multipolygon. Enhancements.

  • Thailand, Khon Kaen, University: For outline replacing relation:multipolygon by relation:boundary. Deleting duplicate tags if node and area.

  • Thailand, Khon Kaen, University: Enhancing Sithan Sports Around. Adding footway, track, path, wall. Enhancements.

  • Thailand Northeast: Enhancing barrier=gate, highway=services, highway=pedestrian. Enhancements.

Adding a meaningful comment is easy if you have made a well defined, even if quite large. change to an area. For example, mapping a hospital, adding a new road or marking an industrial area. It is much harder if you have spent time walking around an area with the map and have a string of minor and unrelated changes to make. For example, adding a missing street name, adding a new mail box, changing the tagging on a footpath because it now allows cycling. Add to that additional minor changes like correcting validation errors where a road doesn’t meet at a junction and it becomes a lot harder to create a meaningful comment. Hence comments like ‘minor changes and amendments’ or ‘added a few POIs’.

I guess the way around this is to create a series of small change sets but I am sure that that is not the way most people work.


If I do a bunch of changes in downtown Orlando, I use a changeset comment of “downtown Orlando”.