code: func (db *DB) Exec(sql string, args ...interface{}) error {
  	db.exclusive.Lock()
  	defer db.exclusive.Unlock()
  
  	s, err := db.statement(sql)
  	if err != nil {
  		return err
  	}
  	_, err = s.Exec(args...)
  	if err != nil {
  		return err
  	}
  
  	return nil
  }
docs: // Execute a named, non-data query (INSERT, UPDATE, DELETE, etc.)