How to query Postgis database to pull all user coordinates from one table, within a polygon from another

I have a Postgis database with polygons in a geom::geometry column. I have table with a 'point' type column of coordinates. I want to pull all of the user_coordinates rows where their coordinate is found within a specific polygon.

I've been researching answers on stackoverflow for days. I've tried all sorts of queries (ST_Contains, ST_Within), most of them telling me that a function I know exists, doesn't. I think it's being thrown off by the point I'm giving it, and wonder what format or type the point column should be in.

Here's a query I'm attempting to give you an idea of what I'm after...

select u.user_id 
from electorial_boundries as e 
INNER JOIN user_coordinates as u on
   ST_Contains(e.geom,ST_GeomFromText('SRID=4326;POINT(u.user_coor))) 
where e.org_id = 595

////Additionally as requested

What is expect:

List all the rows from user_coordinates where the coordinate in user_coordinates.user_coor shows up in the selected polygon from electorial_boundries.geom

Here is the sql for the tables...(sorry, I'm not familiar with how best to use fiddle)

CREATE TABLE public.user_coordinates
(
    id integer NOT NULL GENERATED ALWAYS AS IDENTITY ( INCREMENT 1 START 1 MINVALUE 1 MAXVALUE 2147483647 CACHE 1 ),
    user_id integer NOT NULL,
    user_coor point NOT NULL,
    CONSTRAINT user_coordinates_pkey PRIMARY KEY (id)
)

CREATE TABLE public.electorial_boundries
(
    id integer NOT NULL DEFAULT nextval('electorial_boundries_id_seq'::regclass),
    data_id bigint,
    geom geometry(MultiPolygon,4326),
    district_name character(120) COLLATE pg_catalog."default",
    CONSTRAINT electorial_boundries_pkey PRIMARY KEY (id)
)

The errors are I get that "Function (ST_Contains or ST_Within) Does not exist". But it seems it's just conflicted by the point I'm trying to give it, as an actual coordinate in place of u.user_coor yields some results, though not limited to users in the polygon.

Solution

The column user_coor is of type point, which is a native postgres type that is not directly usable with PostGIS functions.

The error message likely tells you that function ST_Contains(geometry, point) does not exist, which highlights the wrong "point" type as the function exists for two geometries only.

If you can, you should change the column definition to be of type geometry(point,4326).

You can however cast the point to a geometry

select u.user_id 
from electorial_boundries as e 
INNER JOIN user_coordinates as u on
   ST_Contains(e.geom, u.user_coor::geometry) 
where e.org_id = 595