Overpass API developpement

[mmd <>]

Hi Richard,

Am 03.05.2015 um 17:16 schrieb Richard Welty:
> over in the OHM project, we have an interest in extensions to
> Overpass to support temporal queries. we're not looking for
> anything really complex right now, just an ability to do tests
> to see whether or not one date is greater or smaller than another,
> for fields whose values are ISO format dates.

I assume this refers to some date in a tag value, like "lastcheck" [1]?

> but before that comes up, probably it's a good idea to figure
> out what is needed/wanted in the query language, as well
> as what the semantics should be for queries with abbreviated
> dates (e.g., comparing a year to a year-month-day).

There's already a Github ticket [2] on numerical comparison. Based on a
set of operators like "<", "<=", ">" and ">=" I could think about
including date values there as well to have a more generalized approach.

The tricky part will be, how to interpret both tag as well as the query
value: is it a simple numeric value, a width with some unit of measure
(possibly with unit conversion required) or maybe some date value in a
certain format? Next question would be how a reasonable syntax might
look like in Overpass QL/XML?

Best,
mmd


[1] http://taginfo.openstreetmap.org/keys/lastcheck
[2] https://github.com/drolbr/Overpass-API/issues/78