Postgres 12

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create table users (
  id bigserial primary key,
  latitude numeric(7,4) not null,
  longitude numeric(7,4) not null
);
insert into users (latitude, longitude) values
  (43.1234, 22.3456), (44.5, 25.1);
2 rows affected

with users_distance as (
  select
    id,
    ( 6371 * acos( 
                cos( radians(users.latitude) )
              * cos( radians(-22.9035) )
              * cos( radians(-43.2096) - radians(users.longitude) )
              + sin( radians(users.latitude) )
              * sin( radians(-22.9035) ) 
              ) 
    ) as distance
  from users
)
select *
from users
join users_distance ud on users.id = ud.id
where users.id != 41 and ud.distance > 50


id
latitude
longitude
id
distance


1
43.1234
22.3456
1
9929.861265834359

2
44.5000
25.1000
2
10198.394115869187


alter table users add column distance numeric
  generated always as (
    6371 * acos( 
                cos( radians(users.latitude) )
              * cos( radians(-22.9035) )
              * cos( radians(-43.2096) - radians(users.longitude) )
              + sin( radians(users.latitude) )
              * sin( radians(-22.9035) ) 
              )
  ) stored
select * from users;


id
latitude
longitude
distance


1
43.1234
22.3456
9929.86126583436

2
44.5000
25.1000
10198.3941158692

id	latitude	longitude	id	distance
1	43.1234	22.3456	1	9929.861265834359
2	44.5000	25.1000	2	10198.394115869187

id	latitude	longitude	distance
1	43.1234	22.3456	9929.86126583436
2	44.5000	25.1000	10198.3941158692