SQLは、子行を追加または更新できません：外部キー制約が

Question

完全なエラーが失敗します。SQLは、子行を追加または更新できません：。外部キー制約が失敗する（wk3_labをsection、CONSTRAINT fk_course_id_section FOREIGN KEY（Course_ID）がcourse（Course_IDを参照します））

私はこの1つ上の私の知恵の最後に、問題が、何も持っていないされてアイブだし、これまでのところ、私はエラーの解決方法を見つけることができませんでした。ここに私のコードです

-- Nathan Rivera 
-- Week 3 Lab 

-- Drop Tables if they exist 

set foreign_key_checks = 0; 

drop table if exists ZIPCODE; 
drop table if exists INSTRUCTOR; 
drop table if exists STUDENT; 
drop table if exists COURSE; 
drop table if exists SECTION; 
drop table if exists ENROLLMENT; 

set foreign_key_checks = 1; 



create table ZIPCODE 
(

Zip  integer (11), 
City VARCHAR (25) NOT NULL, 
State CHAR (2)  NOT NULL, 
constraint pk_zip primary key (Zip) 
); 

create table INSTRUCTOR 
(

Instructor_ID  integer(6), 
Salutation   varchar(5), 
First_Name   varchar(25) not null, 
Last_Name   varchar(25) not null, 
Street_Address  varchar(50), 
Zip     integer(11) not null, 
constraint pk_instructor_id primary key (Instructor_ID) 
); 




create table STUDENT 
(
Student_ID   integer(6), 
Salutation   varchar(5), 
First_Name   varchar(25) not null, 
Last_Name   varchar(25) not null, 
Street_Address  varchar(50), 
Zip     integer(11) not null, 
Phone    varchar(15) not null, 
Employer   varchar(50), 
Registration_Date date  not null, 
constraint pk_student_id primary key (Student_ID) 
); 




create table COURSE 
(
Course_ID  integer(6), 
Description  varchar(50) not null, 
Cost   decimal(8,2), 
-- on the Data Dictionary it says that Prerequisite is a FK however there are no other tables that have this entry so i cannot create a FK for or from it 
Prerequisite integer(6), 
constraint pk_course_id primary key (Course_ID) 
); 



create table SECTION 
(
Section_ID   integer(8), 
Course_Section_Name integer(6) not null, 
Start_Date_Time  datetime not null, 
Location   varchar(10), 
Capacity   integer(3), 
Instructor_ID  integer(6) not null, 
Course_ID   integer(6) not null, 
constraint pk_section_id primary key (Section_ID) 
); 

create table ENROLLMENT 
(
Section_ID integer(8), 
Student_ID integer(6), 
Enroll_Date date  not null, 
Final_Grade char(1), 
constraint pk_section_id_enrollment primary key (Section_ID, Student_ID) 
); 

alter table INSTRUCTOR add constraint fk_zip_instructor foreign key (Zip) references ZIPCODE (Zip); 
alter table STUDENT add constraint fk_zip_student foreign key (Zip) references ZIPCODE (Zip); 
alter table SECTION add constraint fk_instructor_id_section foreign key (Instructor_ID) references INSTRUCTOR (Instructor_ID); 
alter table SECTION add constraint fk_course_id_section foreign key (Course_ID) references COURSE (Course_ID); 
alter table ENROLLMENT add constraint fk_section_id_enrollment foreign key (Section_ID) references SECTION (Section_ID); 


insert into ZIPCODE (Zip,City,State) 
values 
(7024,"Ft. Lee","NJ"), 
(7047,"North Bergen","NJ"), 
(10005,"New York","NY"), 
(10015,"New York","NY"), 
(10025,"New York","NY"), 
(10035,"New York","NY"), 
(11419,"Richmond Hill","NY"), 
(11435,"Jamaica","NY"); 

insert into STUDENT (Student_ID, Salutation, First_Name, Last_Name, Street_Address, Phone, Employer, Registration_Date, Zip) 
values 
(102,"Mr.","Fred","Crocitto","101-09 120th St.",718-555-5555,"Albert Hildegard Co.",1/22/2007,11419), 
(103,"Ms.","J.","Landry","7435 Boulevard East #45",201-555-5555,"Albert Hildegard Co.",1/22/2007,7047), 
(104,"Ms.","Laetia","Enison","144-61 87th Ave",718-555-5555,"Albert Hildegard Co.",1/22/2007,11435), 
(105,"Mr.","Angel","Moskowitz","320 John St.",201-555-5555,"Alex. & Alexander",1/22/2007,7024), 
(163,"Ms.","Nicole","Gillen","4301 N Ocean #103",904-555-5555,"Oil of America Corp.",2/2/2007,10025), 
(223,"Mr.","Frank","Pace","13 Burlington Dr.",203-555-5555,"Board Utilities",2/8/2007,10025), 
(399,"Mr.","Jerry","Abdou","460 15th St. #4",718-555-5555,"Health Mgmt.Systems",2/23/2007,10025); 

insert into INSTRUCTOR (Instructor_ID, Salutation, First_Name, Last_Name, Street_Address, Zip) 
values 
(101,"Mr","Fernand","Hanks","100 East 87th",10015), 
(102,"Mr","Tom","Wojick","518 West 120th",10025), 
(103,"Ms","Nina","Schorin","210 West 101st",10025), 
(104,"Mr","Gary","Pertez","34 Sixth Ave",10035), 
(105,"Ms","Anita","Morris","34 Maiden Lane",10015), 
(106,"Rev","Todd","Smythe","210 West 101st",10025), 
(107,"Dr","Marilyn","Frantzen","254 Bleeker",10005); 

insert into COURSE (Course_ID,Description,Cost,Prerequisite) 
values 
(330,"Network Administration",1195,130), 
(310,"Operating Systems",1195,NULL), 
(142,"Project Management",1195,20), 
(140,"Systems Analysis",1195,20), 
(130,"Intro to Unix",1195,310), 
(25,"Intro to Programming",1195,140), 
(20,"Intro to Information Systems",1195,NULL); 

insert into SECTION (Section_ID,Course_ID,Course_Section_Name,Start_Date_Time,Location,Instructor_ID,Capacity) 
values 
(81,20,2,"2007-7-24 9:30:00","L210",103,15), 
(86,25,2,"2007-6-10 9:30:00","L210",107,15), 
(89,25,5,"2007-5-15 9:30:00","L509",103,25), 
(92,25,8,"2007-6-13 9:30:00","L509",106,25), 
(104,330,1,"2007-7-14 10:30:00","L511",104,25), 
(119,142,1,"2007-7-14 9:30:00","L211",103,25), 
(155,122,4,"2007-5-4 9:30:00","L210",107,15); 

Answer 1

あなたsectionテーブルの上にfk_course_id_section外部キー制約に違反しています。この制約は、セクションテーブル上のCourse_ID列はもちろんテーブルのCourse_ID列に存在する値を持たなければならないことを意味します。ここで

insert into SECTION (Section_ID,Course_ID,Course_Section_Name,Start_Date_Time,Location,Instructor_ID,Capacity) 
values 
/*...*/ 
(155,122,4,"2007-5-4 9:30:00","L210",107,15); 
/*...*/ 

あなたは122のCourse_IDにしてセクションテーブルにレコードを挿入しています。 Course_IDがコーステーブルに存在しないため、制約に違反しています。

これを解決するには、IDが122のコーステーブルにレコードを挿入するか、間違えた場合に存在するCourse_IDに変更します。

Answer 2

あなたSECTIONテーブルに挿入しようとしているCourseID = 122のエントリが含まれていないコーステーブル。そこで、SQLは正当にSECTIONテーブルへの挿入を拒否します。