var pg = require('pg');

var connectionString = "pg://user:password@host/database";

pg.connect(connectionString, function(err, client) {

    if(err) {
        console.log(err);
    }
    else {
        var query = client.query("SELECT ARRAY['key', 'value', 'key key', 'value value'];");

        query.on('error', function(err) {
            console.log(err);
        });

        query.on('row', function(row) {
            console.log(row);
        });
        query.on('end', function() {
        });
    }

});