code: func (c *Connection) AbortTransaction() error {
  	c.dbMu.RLock()
  	defer c.dbMu.RUnlock()
  	if c.db == nil {
  		return ErrConnectionDoesNotExist
  	}
  	_, err := c.store.execute(c, &ExecuteRequest{[]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.