postgis-cluster-contains.sql

-- postgresql-9.5-postgis-2.2
create table test (name character varying, p geometry(point, 900913), a geometry(Geometry, 900913));
insert into test values ('a', '010100002031BF0D00713D0AD7F54711C1A4703D1A3D965941', null);
insert into test values ('b', '010100002031BF0D0002FB34FAC62E11C1FAF7FB8141965941', '010300002031BF0D00010000000D0000009A9999998B3211C114AE47F13D965941295C8FC2863211C1A4703D5A569659418FC2F528D33011C1EC51B84E5A9659417B14AE47B62F11C1B81E851B5A965941295C8FC2BC2F11C18FC2F5F85D96594114AE47E10D2C11C1295C8FE26F965941EC51B81EF32B11C1666666D6699659417B14AE47D12C11C1F6285CFF139659418FC2F528BA2F11C1F6285C7F14965941B81E85EBBE2F11C11F85EB01279659415C8FC2F5DB2F11C1D7A3702D2C965941F6285C8F2F3011C15C8FC235309659419A9999998B3211C114AE47F13D965941');

select name, st_contains(ST_CollectionHomogenize(c.g), u.p)
    from test u, 
        (select unnest(st_clusterwithin(coalesce(u2.a, st_expand(u2.p, 350)), 250)) g
        from test u2) c order by name;
        
  name | st_contains 
------+-------------
 a    | t
 a    | f
 b    | t
 b    | t
(4 rows)

create temporary table test_g as select unnest(st_clusterwithin(coalesce(a, st_expand(p, 350)), 250)) g from test;
select name, st_contains(ST_CollectionHomogenize(c.g), u.p)
    from test u, test_g c order by name;
osm_gb-#  name | st_contains 
------+-------------
 a    | f
 a    | f
 b    | t
 b    | t
(4 rows)

-- Neither of these outputs appear to be correct, should have one true and one false row each for both a and b