Beyond variable interpolation, fancy SQL generation shortcuts

[summer4096]

More complex interpolation (closer to templating) would be useful. I can't use !geom_hash! in complex queries, but !geom_hash(hgrid.the_geom)! would work if tilesplash supported it. Concerned that it may be a can of worms, though. Still, more advanced substitutions could be useful in all kinds of situations...

WHERE !intersects! --defaults to the_geom

WHERE !intersects(hgrid.the_geom)! --override for fancy queries

WHERE !intersects(the_geom_webmercator, 3857)! --optional transform

SELECT !geojson!, !id! --sensible defaults

SELECT !geojson(hgrid.the_geom)!, !id(hgrid.centroid)! --override stuff, customize stuff

This would let us abstract away some more complicated (but commonly used) geospatial features without making them opaque. Users could get fancy features like polygon deduplication (something not even OSM has figured out) without having to reinvent the wheel, and hopefully without muddying their existing SQL.

If it's extensible enough, I can see this working for more advanced stuff like

SELECT !hexbins! FROM points WHERE !intersects!

[seamusabshere]

maybe better to document strategies in the README with SQL examples

let it marinate with real users, see what they correct, ask questions about or ignore

then add the best/most tested ones as shortcuts