postgis extension for knex
Extension for use postgis functions in knex SQL query builder.
This example show the sql generated by the extension.
const knex = require('knex');
const knexPostgis = require('knex-postgis');
const db = knex({
client: 'postgres'
});
// install postgis functions in knex.postgis;
const st = knexPostgis(db);
/* or:
* knexPostgis(db);
* const st = db.postgis;
*/
// insert a point
const sql1 = db.insert({
id: 1,
geom: st.geomFromText('Point(0 0)', 4326)
}).into('points').toString();
console.log(sql1);
// insert into "points" ("geom", "id") values (ST_geomFromText('Point(0 0)'), '1')
// find all points return point in wkt format
const sql2 = db.select('id', st.asText('geom')).from('points').toString();
console.log(sql2);
// select "id", ST_asText("geom") as "geom" from "points"
// all methods support alias
const sql3 = db.select('id', st.asText(st.centroid('geom')).as('centroid')).from('geometries').toString();
console.log(sql3);
// select "id", ST_asText(ST_centroid("geom")) as "centroid" from "geometries"
a && b
, see postgis documentation
a @ b
, see postgis documentation
a ~ b
, see postgis documentation
const knex = require('knex');
const knexPostgis = require('knex-postgis');
const db = knex({
client: 'postgres'
});
knexPostgis(db);
db.postgisDefineExtras((knex, formatter) => ({
utmzone(geom) {
return knex.raw('utmzone(?)', [formatter.wrapWKT(geom)]);
}
}));
//now you can use st.utmzone function in the same way as predefined functions