Insert POINT into postgres database - postgresql

Question

I need to insert/update a point column type in postgres database.
I'm using node-postgres
The script generated using POSTGRES admin panel shows the update query as
UPDATE public.places SET id=?, user_id=?, business_name=?, alternate_name=?, primary_category=?, categories=?, description=?, address=?, city=?, state=?, country=?, zip=?, point WHERE <condition>;
How do I achieve point from latitude and longitude?
I have seen couple of answers using POSTGIS, but could not get it working.
In the documentation of POSTGRES (https://www.postgresql.org/docs/9.2/static/xfunc-sql.html) it is mentioned we can use point '(2,1)', but this does not work with pg query.
What I have now :
var config = {
user: 'postgres',
database: 'PGDATABASE',
password: 'PGPASSWORD!',
host: 'localhost',
port: 5432,
max: 10,
idleTimeoutMillis: 30000
};
And the update part :
app.post('/updatePlaces', function(req, res, next) {
console.log("Update");
console.log(req.body.places);
pool.query('UPDATE places SET address = $1, alternate_name = $2, business_name = $3, categories = $4, city = $5, country = $6, description = $7, point = $8, primary_category = $9, state = $10, zip = $11', [req.body.places.address, req.body.places.alternate_name, req.body.places.business_name, req.body.places.categories, req.body.places.city, req.body.places.country, req.body.places.description, (req.body.places.point.x, req.body.places.point.y), req.body.places.primary_category, req.body.places.state, req.body.places.zip], function(err, result) {
if(err) {
console.log(err);
return err;
}
res.send(result.rows[0]);
});
});
Tried many different ways for passing point :
(req.body.places.point.x, req.body.places.point.y)
point(req.body.places.point.x, req.body.places.point.y)
point '(2,1)'
All the above throws error. Do I need to use POSTGIS?

Answer 1

This works if you write SQL "directly":
CREATE TEMP TABLE x(p point) ;
INSERT INTO x VALUES ('(1,2)');
INSERT INTO x VALUES (point(3, 4));
SELECT * FROM x ;
Results
(1,2)
(3,4)

Answer 2

After couple of combinations, found out this works.!!
( '(' + req.body.places.point.x + ',' + req.body.places.point.y +')' )
Posting as answer if someone is trying to do this just using node-postgres.
So you can use single-quoted points: insert into x values ( '(1,2)' );
But using insert into x values (point(1,2)); in the query does not work.

Answer 3

I recently came across a similar problem using node-postgres when inserting into a postgis database with a geography (point) column. My solution was to use:
pool.query("INSERT INTO table (name, geography) VALUES ($1, ST_SetSRID(ST_POINT($2, $3), 4326))",
[req.body.name, req.body.lat, req.body.lng ]);

Answer 4

Current versions (Postgres 12, pg 8) should work simply use Postgres's POINT function to set a point column value.
Example:
export async function setPoint(client, x, y, id) {
const sql = `UPDATE table_name SET my_point = POINT($1,$2) WHERE id = $3 RETURNING my_point`;
const result = await client.query(sql, [x, y, id]);
return result.rows[0];
}
await setPoint(client, 10, 20, 5);
Result:
{x: 10.0, y: 20.0}

Answer 5

If you are using pg-promise, then custom types can be formatted automatically, see Custom Type Formatting.
You can introduce your own type like this:
function Point(x, y) {
this.x = x;
this.y = y;
// Custom Type Formatting:
this._rawDBType = true; // to make the type return the string without escaping it;
this.formatDBType = function () {
return 'ST_MakePoint(' + this.x + ',' + this.y + ')';
};
}
At some point you would create your objects:
var p = new Point(11, 22);
And then you can use such variables as regular types:
db.query('INSERT INTO places(place) VALUES(ST_SetSRID($1, 4326))', [p]);
See also: Geometry Constructors.