text: CREATE TABLE `user`(
  	`user_id` VARCHAR(32) NOT NULL,
  	`user_type`TINYINT not NULL,
  	`password` VARCHAR(32) not NULL,
  	PRIMARY KEY (`user_id`,`user_type`)
  	);
  CREATE TABLE `subject`(
  	`subject_id` VARCHAR(32) NOT NULL,
  	`subject_name` VARCHAR(32) NOT NULL,
  	 PRIMARY KEY (`subject_id`)
  	 );
  CREATE TABLE `teacher`(
  	`teacher_id` VARCHAR(32) NOT NULL,
  	`teacher_name` VARCHAR(32) NOT NULL,
  	 PRIMARY KEY (`teacher_id`)
  	 );
  CREATE TABLE `student`(
  	`student_id` VARCHAR(32) NOT NULL,
  	`student_name` VARCHAR(32) NOT NULL,
  	 PRIMARY KEY (`student_id`)
  	 );
  
  CREATE TABLE `template`  (
  	`template_id` varchar(32) NOT NULL,
  	`operation` json not NULL,
  	`section` json not NULL,
  	`choice` json not NULL,
  	PRIMARY KEY (`template_id`)
  );
  
  CREATE TABLE `platform`(
  	`mac_address` varchar(32) NOT NULL,
  	`status` TINYINT NOT NULL DEFAULT 0,
  	PRIMARY KEY (`mac_address`)
  );
  
  CREATE TABLE `peroid`(
  	`peroid_id` tinyint not null,
  	`defination` varchar(64) not null,
  	PRIMARY KEY (`peroid_id`)
  );
  
  CREATE TABLE `semester` (
  	`semester_id` varchar(32) not null,
  	`semester_peroid` int not null,
  	`semester_stage` bit not null,
  	PRIMARY KEY (`semester_id`)
  );