我正在我的数据科学学位课程中学习SQL,并且该任务是第一次执行SQL查询。为此,我必须将SQL入门代码粘贴并运行它。但是,当我这样做时,遇到了无法解决的错误。我的课程在线上,我的教授没有回应,并且由于这不是作业的评分部分,因此我想我可以在这里寻求有关此错误的帮助。
Edit:有人指出我并没有包括所有表格。请查看所有表和所有数据的完整代码。我试图避免用大量代码行淹没这篇文章,但似乎我遗漏了相关信息。见下文。
使用这些代码块创建表:
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 (time_slot_id) references timeslot on delete no action,
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 set null
);
create table instructor (
ID varchar(5),
name varchar(20) not null,
dept_name varchar(20),
salary numeric(8,2) check (salary >10000),
primary key (ID),
foreign key (dept_name) references department on delete set null
);
然后,我将数据添加到讲师和以下部分。旁注,我必须手动设置time_slot_id作为主键,以避免出现错误。
INSERT INTO classroom VALUES ('Innovation Hall', '101', 10);
INSERT INTO classroom VALUES ('Innovation Hall', '327', 30);
INSERT INTO classroom VALUES ('Exploratory Hall', '202', 20);
INSERT INTO classroom VALUES ('Research Hall', '302', 20);
INSERT INTO classroom VALUES ('Arts Center', '212B', 100);
INSERT INTO classroom VALUES ('Research Hall', '310', 30);
INSERT INTO classroom VALUES ('Innovation Hall', '121', 10);
INSERT INTO classroom VALUES ('Innovation Hall', '321', 20);
INSERT INTO classroom VALUES ('Arts Center', '120A', 100);
INSERT INTO classroom VALUES ('Exploratory Hall', '231', 20);
INSERT INTO classroom VALUES ('Innovation Hall', '220', 30);
INSERT INTO department VALUES ('CDS', 'Research Hall', 100000);
INSERT INTO department VALUES ('Music', 'Arts Center', 70000);
INSERT INTO department VALUES ('History', 'Arts Center', 50000);
INSERT INTO department VALUES ('Geography', 'Exploratory Hall', 60000);
INSERT INTO department VALUES ('Biology', 'Exploratory Hall', 85000);
INSERT INTO department VALUES ('Physics', 'Innovation Hall', 90000);
INSERT INTO department VALUES ('Math', 'Exploratory Hall', 55000);
INSERT INTO course VALUES ('CDS-101', 'Intro to CDS', 'CDS', 3);
INSERT INTO course VALUES ('CDS-130', 'Computing for Scientists', 'CDS', 3);
INSERT INTO course VALUES ('CDS-302', 'Databases', 'CDS', 3);
INSERT INTO course VALUES ('CDS-303', 'Data Mining', 'CDS', 3);
INSERT INTO course VALUES ('MUS-100', 'Fundamentals of Music', 'Music', 3);
INSERT INTO course VALUES ('HIS-101', 'History of Western Civilization', 'History', 3);
INSERT INTO course VALUES ('GGS-101', 'Major World Regions', 'Geography', 4);
INSERT INTO course VALUES ('BIO-101', 'Intro to Biology', 'Biology', 3);
INSERT INTO course VALUES ('BIO-301', 'Genetics', 'Biology', 4);
INSERT INTO course VALUES ('PHY-101', 'Intro to Physics', 'Physics', 3);
INSERT INTO course VALUES ('PHY-403', 'Quantum Mechanics', 'Physics', 4);
INSERT INTO course VALUES ('MAT-110', 'Probabilities', 'Math', 3);
INSERT INTO course VALUES ('MAT-114', 'Calculus', 'Math', 4);
INSERT INTO prereq VALUES ('CDS-130', 'CDS-101');
INSERT INTO prereq VALUES ('MAT-114', 'MAT-110');
INSERT INTO prereq VALUES ('PHY-403', 'PHY-101');
INSERT INTO prereq VALUES ('CDS-302', 'CDS-130');
INSERT INTO prereq VALUES ('CDS-302', 'PHY-403');
INSERT INTO prereq VALUES ('CDS-303', 'CDS-302');
INSERT INTO prereq VALUES ('CDS-303', 'MAT-114');
INSERT INTO instructor VALUES ('11111', 'Turing', 'CDS', 950000);
INSERT INTO instructor VALUES ('11112', 'Widom', 'CDS', 100000);
INSERT INTO instructor VALUES ('12121', 'Mozart', 'Music', 75000);
INSERT INTO instructor VALUES ('22222', 'Heraclitus', 'History', 65000);
INSERT INTO instructor VALUES ('12345', 'Eratosthenes', 'Geography', 55000);
INSERT INTO instructor VALUES ('54321', 'Crick', 'Biology', 88000);
INSERT INTO instructor VALUES ('33333', 'Newton', 'Physics', 80000);
INSERT INTO instructor VALUES ('44444', 'Euler', 'Math', 77000);
INSERT INTO instructor VALUES ('55555', 'Euclid', 'Math', 77000);
INSERT INTO timeslot VALUES ('A', 'M', 8, 0 , 9, 15);
INSERT INTO timeslot VALUES ('B', 'M', 10, 0 , 11, 15);
INSERT INTO timeslot VALUES ('C', 'T', 8, 0 , 9, 15);
INSERT INTO timeslot VALUES ('D', 'T', 10, 0 , 11, 15);
INSERT INTO timeslot VALUES ('E', 'T', 11, 15 , 12, 30);
INSERT INTO timeslot VALUES ('F', 'W', 9, 0 , 10, 15);
INSERT INTO timeslot VALUES ('G', 'R', 8, 0 , 10, 15);
INSERT INTO timeslot VALUES ('H', 'R', 15, 0 , 16, 15);
INSERT INTO timeslot VALUES ('I', 'F', 9, 0 , 10, 15);
INSERT INTO section VALUES ('CDS-101', '1', 'Fall', 2019, 'Research Hall', '310', 'A');
INSERT INTO section VALUES ('CDS-130', '1', 'Fall', 2019, 'Innovation Hall', '121', 'B');
INSERT INTO section VALUES ('CDS-302', '1', 'Fall', 2019, 'Innovation Hall', '327', 'C');
INSERT INTO section VALUES ('CDS-302', '2', 'Spring', 2019, 'Innovation Hall', '321', 'C');
INSERT INTO section VALUES ('MUS-100', '1', 'Fall', 2019, 'Arts Center', '120A', 'A');
INSERT INTO section VALUES ('HIS-101', '1', 'Fall', 2019, 'Arts Center', '212B', 'B');
INSERT INTO section VALUES ('GGS-101', '1', 'Fall', 2019, 'Exploratory Hall', '202', 'D');
INSERT INTO section VALUES ('BIO-101', '2', 'Fall', 2019, 'Exploratory Hall', '231', 'E');
INSERT INTO section VALUES ('PHY-403', '1', 'Spring', 2019, 'Innovation Hall', '220', 'F');
INSERT INTO section VALUES ('BIO-101', '2', 'Fall', 2020, 'Exploratory Hall', '231', 'C');
INSERT INTO section VALUES ('PHY-403', '1', 'Spring', 2020, 'Innovation Hall', '220', 'D');
我没问题。最后,我尝试运行此:
INSERT INTO teaches VALUES ('11111', 'CDS-101', '1', 'Fall', 2019);
INSERT INTO teaches VALUES ('11112', 'CDS-130', '1', 'Fall', 2019);
INSERT INTO teaches VALUES ('12121', 'MUS-100', '1', 'Fall', 2019);
INSERT INTO teaches VALUES ('54321', 'BIO-101', '2', 'Fall', 2019);
INSERT INTO teaches VALUES ('33333', 'PHY-403', '1', 'Spring', 2019);
INSERT INTO teaches VALUES ('44444', 'MAT-114', '2', 'Fall', 2019);
错误发生在最后一行。我总是得到:
结果:FOREIGN KEY约束失败在第1行:((注:我之后尝试重新运行它,因此是“第1行”)]INSERT INTO教值('44444','MAT-114','2','Fall',2019);
我检查了每个约束,查看了每一列,但无法弄清楚。我什至进入数据库浏览器精简版的“浏览数据”选项卡中并手动输入数据。虽然我可以输入前4个值,但是当我尝试输入年份时,在弹出框中出现相同的错误。即使单击该框,也将其保留为空白,然后尝试单击一下,仍会出现相同的错误。查看图片。
[请协助...这时我迷路了,很沮丧。
这里有两件事:
让我们从2开始。
错误消息是:
结果:FOREIGN KEY约束失败在第1行:INSERT INTO教值('44444','MAT-114','2','Fall',2019);
这告诉我们查看在teaches
表上定义的外键。
有2:
您的数据中有一个ID为'44444'的讲师,所以这可能不是问题。
但是看起来section
中没有'MAT-114', '2', 'Fall', 2019
所在的行,这很可能是您的问题。
还请注意,图像中也没有用于“ MTH-114”的镜头。