我的mysql工作台脚本是这样的，但是我不能执行它。按钮甚至不显示为活动。有没有在我的代码错误或任何其他问题是由于我没有得到工作完成。创建表格教室（building varchar（15），room_number varchar（7），capacity numeric（4,0），主键（building，room_number））；

create table department
(dept_name      varchar(20), 
 building       varchar(15), 
 budget             numeric(12,2) check (budget > 0),
 primary key (dept_name)
);

create table course
(course_id      varchar(8), 
 title          varchar(50), 
 dept_name      varchar(20),
 credits        numeric(2,0) check (credits > 0),
 primary key (course_id),
 foreign key (dept_name) references department
    on delete set null
);

create table instructor
(ID         varchar(5), 
 name           varchar(20) not null, 
 dept_name      varchar(20), 
 salary         numeric(8,2) check (salary > 29000),
 primary key (ID),
 foreign key (dept_name) references department
    on delete set null
);

create table section
(course_id      varchar(8), 
     sec_id     varchar(8),
 semester       varchar(6)
    check (semester in ('Fall', 'Winter', 'Spring', 'Summer')), 
 year           numeric(4,0) check (year > 1701 and year < 2100), 
 building       varchar(15),
 room_number        varchar(7),
 time_slot_id       varchar(4),
 primary key (course_id, sec_id, semester, year),
 foreign key (course_id) references course
    on delete cascade,
 foreign key (building, room_number) references classroom
    on delete set null
);

create table teaches
(ID         varchar(5), 
 course_id      varchar(8),
 sec_id         varchar(8), 
 semester       varchar(6),
 year           numeric(4,0),
 primary key (ID, course_id, sec_id, semester, year),
 foreign key (course_id,sec_id, semester, year) references section
    on delete cascade,
 foreign key (ID) references instructor
    on delete cascade
);

create table student
(ID         varchar(5), 
 name           varchar(20) not null, 
 dept_name      varchar(20), 
 tot_cred       numeric(3,0) check (tot_cred >= 0),
 primary key (ID),
 foreign key (dept_name) references department
    on delete set null
);

create table takes
(ID         varchar(5), 
 course_id      varchar(8),
 sec_id         varchar(8), 
 semester       varchar(6),
 year           numeric(4,0),
 grade              varchar(2),
 primary key (ID, course_id, sec_id, semester, year),
 foreign key (course_id,sec_id, semester, year) references section
    on delete cascade,
 foreign key (ID) references student
    on delete cascade
);

create table advisor
(s_ID           varchar(5),
 i_ID           varchar(5),
 primary key (s_ID),
 foreign key (i_ID) references instructor (ID)
    on delete set null,
 foreign key (s_ID) references student (ID)
    on delete cascade
);

create table time_slot
(time_slot_id       varchar(4),
 day            varchar(1),
 start_hr       numeric(2) check (start_hr >= 0 and start_hr < 24),
 start_min      numeric(2) check (start_min >= 0 and start_min < 60),
 end_hr         numeric(2) check (end_hr >= 0 and end_hr < 24),
 end_min        numeric(2) check (end_min >= 0 and end_min < 60),
 primary key (time_slot_id, day, start_hr, start_min)
);

create table prereq
(course_id      varchar(8), 
 prereq_id      varchar(8),
 primary key (course_id, prereq_id),
 foreign key (course_id) references course
    on delete cascade,
 foreign key (prereq_id) references course
);