MySQL建表以及显示创建表的sql语句

DROP TABLE IF EXISTS `topic`; CREATE TABLE `topic` (  `TopicId` int(50) NOT NULL auto_increment,  `Topic_BoardId` int(10) NOT NULL,  `Topic_StudentId` int(10) NOT NULL,  `TopicTitle` varchar(1000) NOT NULL,  `TopicContent` varchar(6000) NOT NULL,  `TopicSendTime` varchar(30) NOT NULL,  PRIMARY KEY  (`TopicId`),  FOREIGN KEY (`Topic_BoardId`) REFERENCES `board` (`BoardId`) ON DELETE CASCADE ON UPDATE CASCADE,  FOREIGN KEY (`Topic_StudentId`) REFERENCES `student` (`StudentId`) ON DELETE CASCADE ON UPDATE CASCADE) ENGINE=InnoDB DEFAULT CHARSET=gb2312