Method query

testing/postgres-client-tests/node/database.js:10–17

(sql, args)

  }

  query(sql, args) {
    return new Promise((resolve, reject) => {
      this.client.query(sql, args, (err, rows) => {
        if (err) return reject(err);
        return resolve(rows);
      });
    });
  }

  close() {
    this.client.end((err) => {