request for api on count of entries

[rlzijdeman]

Whilst advocating the WHGazetteer, I was trying to find the number of entities of featureClass 'p' in a given region. Could that be added as a feature of the API? Perhaps whilst allowing for a time range? So something along the lines of:

/api/db/?N - total number of places in WHGazetteer
/api/db/?N&ccode="NL" - total number of places in the Netherlands
/api/db/?N&?ccode="NL"&?year>1500 - total number of places in the Netherlands that existed at some point after 1500

Perhaps featureless itself ought to be part of the query, but to honest, I guess most will be interested in p or a.

[kgeographer]

Straightforward to implement. Raises an issue #45 -- speed of queries against the database (which has everything) is much worse than against an Elasticsearch index. Maybe further use of a separately and automatically maintained index of some basic info from the database. Upon making a dataset public, its simplified records are added to a sort of hash index. They would have to be scrubbed or replaced if/when the dataset was updated or removed.

At present, the database indexes have not been optimized; it's possible if they were, speed of such queries against the database would be acceptable.