MySQL基础----触发器

废话不多说。自己看看吧.等以后有时间了再完善完善.^-^

CREATE TABLE `vardata` (
  `Id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) DEFAULT NULL,
  `time` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
  `data` double(15,5) DEFAULT '-601.00000',
  PRIMARY KEY (`Id`,`time`),
  UNIQUE KEY `unique` (`name`,`time`)
)

CREATE TABLE `vardata_compute` (
  `Id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) DEFAULT NULL,
  `time` datetime DEFAULT NULL,
  `data` double(15,5) DEFAULT NULL,
  PRIMARY KEY (`Id`)
) 

DROP TRIGGER IF EXISTS trigger_insert_59data;
CREATE TRIGGER trigger_insert_59data 
AFTER INSERT 
ON vardata 
FOR EACH ROW 
BEGIN
     DECLARE time_59 DateTime;              
     SET time_59 = NEW.time-INTERVAL 1 SECOND; 
     IF MINUTE(NEW.time)=0 AND SECOND(NEW.time)=0 THEN
        INSERT INTO vardata_compute SET name=NEW.name,time=time_59,data=NEW.data;  
     END IF;   
END;

DROP TRIGGER IF EXISTS trigger_delete_59data;
CREATE TRIGGER trigger_delete_59data 
AFTER DELETE 
ON vardata 
FOR EACH ROW 
BEGIN
     DECLARE time_59 DateTime;     
     SET time_59 = OLD.time-INTERVAL 1 SECOND; 
     IF MINUTE(OLD.time)=0 AND SECOND(OLD.time)=0 THEN     
        DELETE FROM vardata_compute WHERE time=time_59 AND name=old.name;
     END IF;   
END;

DROP TRIGGER IF EXISTS trigger_update_59data;
CREATE TRIGGER trigger_update_59data 
AFTER UPDATE 
ON vardata 
FOR EACH ROW 
BEGIN
     DECLARE time_59 DateTime;     
     SET time_59 = NEW.time-INTERVAL 1 SECOND; 
     IF MINUTE(NEW.time)=0 AND SECOND(NEW.time)=0 THEN          
        UPDATE vardata_compute SET data=NEW.data WHERE time=time_59 AND name=NEW.name;
     END IF;   
END;