alter table tb_course add selected int(3) not null default 0 check ( selected between 0 and total_people ) comment ‘课程已选人数‘;
报错：Column check constraint ‘tb_course_chk_3‘ references other column. 列检查约束不能引用其他列
alter table tb_course add selected int(3) not null default 0 comment ‘课程已选人数‘; alter table tb_course add constraint ck_selected check ( tb_course.selected between 0 and tb_course.total_people); #total_people是另一个列，该列被引用
mysql 3813：Column check constraint 'tb_course_chk_3' references other column.