Add postgis test

nix/tests/expected/postgis.out

@@ -0,0 +1,59 @@
+create schema v;
+-- create a table to store geographic points
+create table v.places (
+    id serial primary key,
+    name text,
+    geom geometry(point, 4326)  -- using WGS 84 coordinate system
+);
+-- insert some sample geographic points into the places table
+insert into v.places (name, geom)
+values
+  ('place_a', st_setsrid(st_makepoint(-73.9857, 40.7484), 4326)),  -- latitude and longitude for a location
+  ('place_b', st_setsrid(st_makepoint(-74.0060, 40.7128), 4326)),  -- another location
+  ('place_c', st_setsrid(st_makepoint(-73.9687, 40.7851), 4326));  -- yet another location
+-- calculate the distance between two points (in meters)
+select
+  a.name as place_a,
+  b.name as place_b,
+  st_distance(a.geom::geography, b.geom::geography) as distance_meters
+from
+  v.places a,
+  v.places b
+where
+  a.name = 'place_a'
+  and b.name = 'place_b';
+ place_a | place_b | distance_meters 
+---------+---------+-----------------
+ place_a | place_b |   4309.25283351
+(1 row)
+
+-- find all places within a 5km radius of 'place_a'
+select
+  name,
+  st_distance(
+    geom::geography,
+    (
+      select
+        geom
+      from
+        v.places
+      where
+        name = 'place_a'
+    )::geography) as distance_meters
+from
+  v.places
+where
+  st_dwithin(
+    geom::geography,
+    (select geom from v.places where name = 'place_a')::geography,
+    5000
+  )
+  and name != 'place_a';
+  name   | distance_meters 
+---------+-----------------
+ place_b |   4309.25283351
+ place_c |    4320.8765634
+(2 rows)
+
+drop schema v cascade;
+NOTICE:  drop cascades to table v.places

nix/tests/sql/postgis.sql

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+create schema v;
+
+-- create a table to store geographic points
+create table v.places (
+    id serial primary key,
+    name text,
+    geom geometry(point, 4326)  -- using WGS 84 coordinate system
+);
+
+-- insert some sample geographic points into the places table
+insert into v.places (name, geom)
+values
+  ('place_a', st_setsrid(st_makepoint(-73.9857, 40.7484), 4326)),  -- latitude and longitude for a location
+  ('place_b', st_setsrid(st_makepoint(-74.0060, 40.7128), 4326)),  -- another location
+  ('place_c', st_setsrid(st_makepoint(-73.9687, 40.7851), 4326));  -- yet another location
+
+-- calculate the distance between two points (in meters)
+select
+  a.name as place_a,
+  b.name as place_b,
+  st_distance(a.geom::geography, b.geom::geography) as distance_meters
+from
+  v.places a,
+  v.places b
+where
+  a.name = 'place_a'
+  and b.name = 'place_b';
+
+-- find all places within a 5km radius of 'place_a'
+select
+  name,
+  st_distance(
+    geom::geography,
+    (
+      select
+        geom
+      from
+        v.places
+      where
+        name = 'place_a'
+    )::geography) as distance_meters
+from
+  v.places
+where
+  st_dwithin(
+    geom::geography,
+    (select geom from v.places where name = 'place_a')::geography,
+    5000
+  )
+  and name != 'place_a';
+
+drop schema v cascade;