code: func (c *Conn) AbortTransaction() error {
  	_, err := c.Execute([]string{`ROLLBACK`}, false, false)
  	return err
  }
docs: // AbortTransaction aborts -- rolls back -- any active transaction. Calling code
  // should know exactly what it is doing if it decides to call this function. It
  // can be used to clean up any dangling state that may result from certain
  // error scenarios.