Use bounding box from PostGIS in vanilla Postgres query - sql

Question

I have a db structure that is vanilla Postgres:
CREATE TABLE IF NOT EXISTS locations (
name text NOT NULL,
lat double precision NOT NULL,
lng double precision NOT NULL,
);
CREATE INDEX ON locations(lat,lng);
When I want to calculate all locations in a bounding box where I have the lower left and upper right corners I use the following query:
SELECT * FROM locations
WHERE lat >= min_lat AND
WHERE lat <= max_lat AND
WHERE lng >= min_lng AND
WHERE lng <= max_lng;
Now, I want to generate a bounding box given a point and use the bounding box result in the locations query. I'm using the following PostGIS query to generate a bounding box:
SELECT
ST_Extent(
ST_Envelope(
ST_Rotate(
ST_Buffer(
ST_GeomFromText('POINT (-87.6297982 41.8781136)',4326)::GEOGRAPHY,160934)::GEOMETRY,0)));
Result: BOX(-89.568160053866 40.4285062983089,-85.6903925527536 43.3273499289221)
However, I'm not sure how use the results from the PostGIS query bounding box into the vanilla lat / lng Postgres query in one call. Any ideas on how to merge the two? Preferably such that the index is preserved.

Answer 1

If you want to get the bbox coordinates as separated values you might wanna take a look at ST_XMax, ST_YMax, ST_XMin, ST_YMin. The following CTE, that embeds your query, should give you an idea:
WITH j (geom) AS (
SELECT
ST_Extent(ST_Envelope(
ST_Rotate(ST_Buffer(
ST_GeomFromText('POINT(-87.6297982 41.8781136)',4326)::GEOGRAPHY,160934)::GEOMETRY,0)))
)
SELECT
ST_XMax(geom),ST_YMax(geom),
ST_XMin(geom),ST_YMin(geom)
FROM j
st_xmax | st_ymax | st_xmin | st_ymin
-------------------+-----------------+-------------------+------------------
-85.6903925527536 | 43.327349928921 | -89.5681600538661 | 40.4285062983098
Side note: Storing geometry values as numbers might look straightforward but it is hardly ever the better choice - specially when dealing with polygons! So I would really suggest you to store these values as geometry or geography, which might seem complex at first a glance but definitely pays off on the long run.
This answer might shed a light on distance/containment queries involving polygons: Getting all Buildings in range of 5 miles from specified coordinates