CREATE TABLE IF NOT EXISTS `History` (
  `Time` int(11) NOT NULL,
  `Period` int(11) NOT NULL,
  `Measure` int(11) NOT NULL,
  `Server` int(11) NOT NULL,
  `Minimum` double NOT NULL,
  `Average` double NOT NULL,
  `Maximum` double NOT NULL,
  UNIQUE KEY `Time_2` (`Time`,`Period`,`Measure`,`Server`),
  KEY `Time` (`Time`),
  KEY `Measure` (`Measure`),
  KEY `Server` (`Server`),
  KEY `Period` (`Period`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8;

ALTER TABLE `Task` CHANGE `TimeCreate` `TimeCreate` DATETIME NULL ,
CHANGE `TimeStart` `TimeStart` DATETIME NULL ,
CHANGE `TimeEnd` `TimeEnd` DATETIME NULL ;

ALTER TABLE `Task` ADD `Error` TEXT NOT NULL ;

