Document DB - ST_DISTANCE

问题

Would a query like

SELECT TOP 1 * ST_DISTANCE etc 

or more specifically

SELECT TOP 1 * FROM c WHERE ST_DISTANCE(c.AssetLocation, { 'type': 'Point', 'coordinates': [115.58, 21.84] }) < 49999

return the closest object, and if not, how could I order by distance?

Thanks,

Ian

回答1:

DocumentDB does not natively support nearest or ORDER BY using Geo-Spatial index yet.

The best approach for ORDER BY is to project (SELECT) the distance in the query and sort it either client-side or via a stored procedure (reduces the latency cost of multiple round trips).

For a large data set, you can optimize nearest by adding a filter (WHERE) on distance beginning with a small value, and iterating / stepping through increasing distance values until the first points are found.

来源：https://stackoverflow.com/questions/37262001/document-db-st-distance