text: INSERT INTO `t_global_data` VALUES('pve_difficult_data', '[]') ;
  INSERT INTO `t_global_data` VALUES('heroStar_data', '[]') ; 
  
  ALTER TABLE `t_user` ADD COLUMN `platform` VARCHAR (15) NULL AFTER `lastAccessedTime` ;
  
  DROP TABLE IF EXISTS `t_cdkey` ;
  CREATE TABLE `t_cdkey` (
   `cdkey` VARCHAR (20) NOT NULL,
   `batch` INT (4) DEFAULT NULL,
   `itemId` VARCHAR (8) NOT NULL,
   `beginTime` BIGINT (20) NOT NULL,
   `endTime` BIGINT (20) NOT NULL,
   `state` INT (4) NOT NULL,
   `platform` VARCHAR (15) DEFAULT NULL,
   `creationTime` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP, PRIMARY KEY (`cdkey`)
  ) ENGINE = INNODB DEFAULT CHARSET = utf8 ;
  
  DROP TABLE IF EXISTS `t_plog` ;
  CREATE TABLE `t_plog` (
   `uid` INT (11) NOT NULL,
   `changeValue` INT (10) NOT NULL,
   `changeType` VARCHAR (10) NOT NULL,
   `description` LONGTEXT,
   `creationTime` BIGINT (20) DEFAULT NULL
  ) ENGINE = INNODB DEFAULT CHARSET = utf8 ;
  CREATE INDEX `uid` ON `t_plog` (`uid`)