On Sun, 18 Feb 2018 00:35:18 +0100 hmidi slim <hmidi.slim2@xxxxxxxxx> wrote: > Hi, > I have two tables: establishment which contains these columns: id, name, > longitude, latitude, geom (Geometric column) > Product contains: id, name, establishment_id > First of all I want to select the establishment within a radius. > I run this query: > select e.name, e1.name > from establishment as e, establishment as e1 > where e.id <> e1.id > and e1.id = 1 > and ST_DWithin(geom, ST_MakePoint(e1.longitude, e1.latitude)::geography, > 1000) > > The result of this query returns all the establishment within a radius 1KM > from from a given establishment which has an id = 1. > > After that I want to get the product's name of each establishment from the > query's result. > > Is there an other optimized solution to make a query such this: > select * from ( > select e.name, e1.name, e.id > from establishment as e, establishment as e1 > where e.id <> e1.id > and e1.id = 1 > and ST_DWithin(geom, ST_MakePoint(e1.longitude, e1.latitude)::geography, > 1000)) as tmp inner join product as p on p.establishment_id = tmp.id Did you not see my earlier response? -- Bill Moran
