[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fyxMPM8wlpH-OYBJbCUius8mI445AyEo-guvShW9gTV4":3},{"answer":4,"createTime":5,"id":6,"options":7,"origin":12,"question":19,"related":20,"source":30,"type":31},[],"2023-06-16 14:28:51",65134605,[8,9,10,11],"create table sc ( sno char(9) primary key, cno char(4) primary key, grade smallint )","create table sc ( sno char(9) primary key, cno char(4) , grade smallint )","create table sc ( sno char(9) , cno char(4) primary key, grade smallint )","create table sc ( sno char(9) , cno char(4) , grade smallint, primary key (sno,cno) )",{"count":13,"courseId":14,"courseImg":15,"courseName":16,"workId":17,"workName":18},10,"b8e87be6a0a74bd76f5f9dfdd209bae1","https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F9c1e48361b00f3ee2086f4e259ed792b.jpg","数据库系统概论2023","work_27019804","第五章数据库完整性作业.xls","将sc表中的sno、cno属性组定义为主码",[21,32,35,44,52,61,69,78,87,96],{"answer":22,"createTime":5,"id":23,"options":24,"question":29,"source":30,"type":31},[],65134604,[25,26,27,28],"create table student ( sno char(9) foreign key, sname char(20) not null, ssex char(2), sage smallint, sdept char(20) )","create table student ( sno char(9) primary key, sname char(20) not null, ssex char(2), sage smallint, sdept char(20) )","create table student ( sno char(9) , sname char(20) primary key, ssex char(2), sage smallint, sdept char(20) )","create table student ( sno char(9) , sname char(20) not null, ssex char(2), sage smallint, sdept char(20) )","将Student表中的Sno属性定义为主码","v1",0,{"answer":33,"createTime":5,"id":6,"options":34,"question":19,"source":30,"type":31},[],[8,9,10,11],{"answer":36,"createTime":5,"id":37,"options":38,"question":43,"source":30,"type":31},[],65134606,[39,40,41,42],"create table sc ( sno char(9) not null, cno char(9) not null, grade smallint, primary key(sno,cno), foreign key (sno) references student(sno) )","create table sc ( sno char(9) not null, cno char(9) not null, grade smallint, primary key(sno,cno), foreign key (cno) references student(cno) )","create table sc ( sno char(9) not null, cno char(9) not null, grade smallint, primary key(sno,cno), foreign key (sno) references student(sno), foreign key (cno) references student(cno) )","create table sc ( sno char(9) not null, cno char(9) not null, grade smallint, primary key(sno,cno) )","定义sc表中的参照完整性,sno,cno分别参照应用student表的主码和course表的主码",{"answer":45,"createTime":5,"id":46,"options":47,"question":51,"source":30,"type":31},[],65134607,[26,48,49,50],"create table student ( sno char(9) primary key, sname char(20) not null, ssex char(2) in('男','女'), sage smallint, sdept char(20) )","create table student ( sno char(9) primary key, sname char(20) not null, ssex char(2) check in('男','女'), sage smallint, sdept char(20) )","create table student ( sno char(9) primary key, sname char(20) not null, ssex char(2) check(ssex in('男','女')), sage smallint, sdept char(20) )","student表的ssex只允许取"男"或"女"",{"answer":53,"createTime":5,"id":54,"options":55,"question":60,"source":30,"type":31},[],65134608,[56,57,58,59],"create table sc ( sno char(9) , cno char(4) , grade smallint, primary key(sno,cno), foreign key(sno) references student(sno), foreign key(cno) references student(cno), )","create table sc ( sno char(9) , cno char(4) , grade smallint check(0,100), primary key(sno,cno), foreign key(sno) references student(sno), foreign key(cno) references student(cno), )","create table sc ( sno char(9) , cno char(4) , grade smallint check(grade>=0 and grade<=100), primary key(sno,cno), foreign key(sno) references student(sno), foreign key(cno) references student(cno), )","create table sc ( sno char(9) , cno char(4) , grade smallint check(0 and 100), primary key(sno,cno), foreign key(sno) references student(sno), foreign key(cno) references student(cno), )","sc表的grade的值应该在0和100之间",{"answer":62,"createTime":5,"id":63,"options":64,"question":68,"source":30,"type":31},[],65134609,[26,65,66,67],"create table student ( sno char(9) primary key, sname char(20) not null, ssex char(2), sage smallint, sdept char(20), check(ssex='男' and sname not like 'Ms.%') )","create table student ( sno char(9) , sname char(20) not null, ssex char(2), sage smallint, sdept char(20), check(ssex='男' and sname not like 'Ms.%') )","create table student ( sno char(9) primary key, sname char(20) not null, ssex char(2), sage smallint, sdept char(20), check(ssex='女' or sname not like 'Ms.%') )","当学生的性别是男时,其名字不能以Ms.打头",{"answer":70,"createTime":5,"id":71,"options":72,"question":77,"source":30,"type":31},[],65134610,[73,74,75,76],"create table student ( sno char(9) primary key, sname char(20) , ssex char(2) constraint c3 check(ssex in('男','女')), sage smallint, sdept char(20) )","create table student ( sno char(9) primary key, sname char(20) constraint c1 not null, ssex char(2) constraint c3 check(ssex in('男','女')), sage smallint, sdept char(20) )","create table student ( sno char(9) primary key, sname char(20) constraint c1 not null, ssex char(2) constraint c3 check(ssex in('男','女')), sage smallint constraint c2 check(sage<30), sdept char(20) )","create table student ( sno char(9) primary key, sname char(20) constraint c1 not null, ssex char(2) constraint c3 check(ssex in('男','女')), sage smallint constraint c2 check(sage<30), sdept char(20) check )","建立学生登记表student,要求姓名不能取空值,年龄小于30,性别只能是"男"或"女"",{"answer":79,"createTime":5,"id":80,"options":81,"question":86,"source":30,"type":31},[],65134611,[82,83,84,85],"drop table student","delete table student","alter table student drop constraint","alter table student drop constraint c3","去掉student表中对性别的限制(第7题已在student表中建立对性别的限制)",{"answer":88,"createTime":5,"id":89,"options":90,"question":95,"source":30,"type":31},[],65134612,[91,92,93,94],"not","not null","not unique","not check","在创建表时可以根据应用要求定义属性上的约束条件,其中列值非空的约束关键词是",{"answer":97,"createTime":5,"id":98,"options":99,"question":102,"source":30,"type":31},[],65134613,[100,101,92,93],"unique","null","在创建表时可以根据应用要求定义属性上的约束条件,其中列值唯一的约束关键词是"]