Question

我正在尝试在MySQL中编写一个触发器，我需要设置几个变量的值。我需要放入这些变量的值来自现有表中的一行（不担心多行，只会有一行）：

DELIMITER |

CREATE TRIGGER ins_move_to_hist BEFORE INSERT ON EndOfDay
FOR EACH ROW
BEGIN
 DECLARE _RowsMatching int;
 DECLARE _EodId  int(10) unsigned;
  DECLARE _Open  decimal(6,4);
  DECLARE _High  decimal(6,4);
  DECLARE _Low   decimal(6,4);
  DECLARE _Close  decimal(6,4);
  DECLARE _Volume  int(10) unsigned;
  DECLARE _mtime  datetime;

 SELECT _RowsMatching = Count(*), 
  EodId as _EodId, 
  Open as _Open,
  High as _High,
  Low as _Low,
  Close as _Close,
  Volume as _Volume,
  mtime as _mtime
 from EndOfDay 
 where DateId = NEW.DateId
  and TickerId = NEW.TickerId;

但是，触发器不允许选择结果（我不需要）。所以，当我运行创建脚本时，它给了我这个错误：

不允许返回结果集来自触发器。

Answer 1

我相信你只需要将你的as语句改为语句。

更新：正如比尔在下面纠正我的那样，INTO语句的格式更像是插入语句，即;列列表INTO值列表。

SELECT Count(*), EodId, Open, High, Low, Close, Volume, mtime 
INTO _RowsMatching, _EodId, _Open, _High, _Low, _Close, _Volume, _mtime
...

谢谢，比尔。 ;）

MySQL BEFORE INSERT触发器选择多个变量？

1 个答案: