I can't get the GenreID foreign key on the Album table to work. Anyone know why?
CREATE TABLE ArtistBand
(
ArtistID INT AUTO_INCREMENT PRIMARY KEY,
BandName VARCHAR(255) NOT NULL,
NameOfMembers VARCHAR(255),
NumberOfMembers INT
);
CREATE TABLE Genre
(
GenreID INT AUTO_INCREMENT PRIMARY KEY,
GenreType VARCHAR(255) NOT NULL,
AlbumID INT,
FOREIGN KEY(AlbumID) REFERENCES Album(AlbumID)
);
CREATE TABLE Album
(
AlbumID INT AUTO_INCREMENT PRIMARY KEY,
Name VARCHAR (255) NOT NULL,
ReleaseDate DATE NOT NULL,
Producers VARCHAR (255),
ArtistID INT,
GenreID INT,
FOREIGN KEY(ArtistID) REFERENCES ArtistBand(ArtistID),
FOREIGN KEY (GenreID) REFERENCES Genre (GenreID)
);
Get rid of the circular foreign key reference between Genre and Album. Logically speaking, the reference from Genre to Album doesn't make any sense anyway :).
CREATE TABLE ArtistBand (
ArtistID INT AUTO_INCREMENT PRIMARY KEY,
BandName VARCHAR(255) NOT NULL,
NameOfMembers VARCHAR(255),
NumberOfMembers INT
);
CREATE TABLE Genre(
GenreID INT AUTO_INCREMENT PRIMARY KEY,
GenreType VARCHAR(255) NOT NULL
);
CREATE TABLE Album (
AlbumID INT AUTO_INCREMENT PRIMARY KEY,
Name VARCHAR (255) NOT NULL,
ReleaseDate DATE NOT NULL,
Producers VARCHAR (255),
ArtistID INT,
GenreID INT,
FOREIGN KEY(ArtistID) REFERENCES ArtistBand(ArtistID),
FOREIGN KEY (GenreID) REFERENCES Genre (GenreID)
);
if use sql server : auto_increment be modified to identity
CREATE TABLE ArtistBand (
ArtistID INT identity(1,1) PRIMARY KEY,
BandName VARCHAR(255) NOT NULL,
NameOfMembers VARCHAR(255),
NumberOfMembers INT
);
CREATE TABLE Genre(
GenreID INT identity(1,1) PRIMARY KEY,
GenreType VARCHAR(255) NOT NULL
);
CREATE TABLE Album (
AlbumID INT identity(1,1) PRIMARY KEY,
Name VARCHAR (255) NOT NULL,
ReleaseDate DATE NOT NULL,
Producers VARCHAR (255),
ArtistID INT,
GenreID INT,
FOREIGN KEY(ArtistID) REFERENCES ArtistBand(ArtistID),
FOREIGN KEY (GenreID) REFERENCES Genre (GenreID)
);
Related
CREATE TABLE student
(
student_id INT PRIMARY KEY,
first_name VARCHAR(40) NOT NULL,
last_name VARCHAR(40) NOT NULL,
birth_day DATE NOT NULL,
sex VARCHAR(1) NOT NULL,
student_email_address VARCHAR(40) NOT NULL UNIQUE,
student_password VARCHAR(10) NOT NULL UNIQUE,
student_nick_name VARCHAR(10) NOT NULL,
student_qualification VARCHAR(10) NOT NULL,
student_documents VARCHAR(255) NOT NULL,
student_image VARCHAR(100) NOT NULL
);
CREATE TABLE student_feedback
(
sr_no BIGSERIAL PRIMARY KEY,
student_id INT NOT NULL,
feedback_type VARCHAR(10) NOT NULL,
feedback_text VARCHAR(200) NOT NULL,
FOREIGN KEY (student_id) REFERENCES student(student_id)
);
CREATE TABLE online_exam
(
exam_id INT PRIMARY KEY,
exam_title VARCHAR(20) UNIQUE NOT NULL,
exam_duration_min INT NOT NULL,
total_questions INT NOT NULL,
marks_per_right_answer INT NOT NULL,
marks_per_wrong_answer INT NOT NULL,
passing_marks INT NOT NULL,
exam_status VARCHAR(2)
);
CREATE TABLE exam_subjects
(
sub_id INT,
exam_id INT,
sub_name VARCHAR(20) NOT NULL,
sub_desc VARCHAR(20) NOT NULL,
UNIQUE(sub_id,exam_id),
PRIMARY KEY(sub_id,exam_id),
FOREIGN KEY (exam_id) REFERENCES online_exam(exam_id) ON DELETE CASCADE
);
CREATE TABLE sub_questions
(
sub_id1 INT,
ques_id INT,
ques_text VARCHAR(150) NOT NULL,
ques_attachments VARCHAR(255),
option_1 VARCHAR(20) NOT NULL,
option_2 VARCHAR(20) NOT NULL,
option_3 VARCHAR(20) NOT NULL,
option_4 VARCHAR(20) NOT NULL,
UNIQUE(sub_id1,ques_id),
PRIMARY KEY (sub_id1,ques_id),
FOREIGN KEY (sub_id1) REFERENCES exam_subjects(sub_id) ON DELETE CASCADE
);
CREATE TABLE ques_answers
(
ans_id INT,
ques_id INT,
ans VARCHAR(20) NOT NULL,
PRIMARY KEY (ans_id,ques_id),
FOREIGN KEY (ques_id) REFERENCES sub_questions(ques_id) ON DELETE CASCADE
);
CREATE TABLE exam_registration
(
student_id INT,
exam_id INT,
exam_date_time TIMESTAMP NOT NULL,
PRIMARY KEY (student_id,exam_id),
FOREIGN KEY (student_id) REFERENCES student(student_id) ON DELETE CASCADE,
FOREIGN KEY (exam_id) REFERENCES online_exam(exam_id) ON DELETE CASCADE
);
CREATE TABLE exam_result
(
student_id INT,
exam_id INT,
sub_id INT,
marks_scored INT NOT NULL,
correct_ques INT NOT NULL,
wrong_ques INT NOT NULL,
grade VARCHAR(10) NOT NULL,
PRIMARY KEY(student_id,exam_id,sub_id),
FOREIGN KEY (student_id) REFERENCES student(student_id) ON DELETE CASCADE,
FOREIGN KEY (exam_id) REFERENCES online_exam(exam_id) ON DELETE CASCADE,
FOREIGN KEY (sub_id) REFERENCES exam_subjects(sub_id) ON DELETE CASCADE
);
Output :
CREATE TABLE,
CREATE TABLE,
CREATE TABLE,
CREATE TABLE,
There is no unique constraint matching given keys for referenced table "exam_subjects", relation "sub_questions" do not exist,
CREATE TABLE,
There is no unique constraint matching given keys for referenced table "exam_subjects".
Why am I getting "there is no unique..." error in postgresql? How to solve it? Please help.
In your table exam_subjects the primary key is a compossed key (PRIMARY KEY(sub_id, exam_id))
Therefore, your table sub_questions must have both columns to create the constraint, otherwise you get the error about unique constraints (or you can create a unique field acting as primary key, and create a unique index on both columns sub_id and exam_id)
This is code to create the beginnings of a book library database with Microsoft SQL Server Management Studio.
CREATE DATABASE BOOK_LIBRARY
CREATE TABLE LIBRARY_USER
(
usr_id int not null primary key,
f_name varchar(30) not null,
m_init char(1),
l_name varchar(30) not null,
balance decimal(6,2),
join_date date,
addrss_1 varchar(30) not null,
addrss_2 varchar(30),
city varchar(30) not null,
addrss_state char(2) not null,
zip_code varchar(10) not null,
email varchar(30)
);
CREATE TABLE LIBRARY_TRANSACTIONS
(
transaction_id int not null primary key,
maximum_borrow_duration int not null,
strt_date date not null,
actual_return_date date not null,
borrow_usr_id int not null,
foreign key (borrow_usr_id) references LIBRARY_USER(usr_id)
);
CREATE TABLE BOOKS
(
isbn varchar(17) not null primary key,
title varchar(30) not null,
number_of_copies int not null,
Author varchar(30) not null,
Number_of_pages int not null,
publish_year int not null,
book_type varchar(20)
);
CREATE TABLE DIGITAL_BOOKS
(
digital_id int not null primary key,
format varchar(30) not null,
size_mb int not null,
digital_isbn varchar(17) not null,
foreign key(digital_isbn) references BOOKS(isbn)
);
CREATE TABLE PHYSICAL_BOOKS
(
physical_id int not null primary key,
condition varchar(20) not null,
physical_isbn varchar(17) not null,
foreign key(physical_isbn) references BOOKS(isbn)
);
CREATE TABLE BOOK_COPY
(
digi_id int not null,
phys_id int not null,
primary key(digi_id, phys_id),
foreign key(digi_id) references DIGITAL_BOOKS(digital_id),
foreign key(phys_id) references PHYSICAL_BOOKS(physical_id)
);
CREATE TABLE CONTNS
(
trans_id int not null primary key,
digi_id int not null,
phys_id int not null,
foreign key(digi_id) references BOOK_COPY(digi_id),
foreign key(phys_id) references BOOK_COPY(phys_id)
);
Despite me being able to look and see that digi_id and phys_id are in fact primary keys of the book_copy table, I keep getting this error:
Msg 1776, Level 16, State 0, Line 66
There are no primary or candidate keys in the referenced table 'BOOK_COPY' that match the referencing column list in the foreign key 'FK__CONTNS__digi_id__37A5467C'.
Msg 1750, Level 16, State 1, Line 66
Could not create constraint or index. See previous errors.
Am I missing something obvious? I'm just starting out with using this program, so any help is greatly appreciated.
Here:
CREATE TABLE CONTNS
(
trans_id int not null primary key,
digi_id int not null,
phys_id int not null,
foreign key(digi_id) references BOOK_COPY(digi_id),
foreign key(phys_id) references BOOK_COPY(phys_id)
);
You are creating two foreign keys to parent table BOOK_COPY. But that table has a compound primary key (ie a multi-column primary key)
CREATE TABLE BOOK_COPY
(
digi_id int not null,
phys_id int not null,
primary key(digi_id, phys_id), --> here
...
)
As a consequence, you need a compound foreign key:
CREATE TABLE CONTNS
(
trans_id int not null primary key,
digi_id int not null,
phys_id int not null,
foreign key(digi_id, phys_id) references BOOK_COPY(digi_id, phys_id)
);
CREATE TABLE singer(
name varchar(50) primary key,
email varchar(50) not null,
account_number varchar(50) not null,
balance int not null
);
create table song(
id int primary key,
name varchar(50) not null,
singer varchar(50) foreign key references singer,
producer varchar(50) not null,
album varchar(50) not null,
total_sell int not null
);
CREATE TABLE producer(name VARCHAR(20) PRIMARY KEY);
ALTER TABLE song ALTER COLUMN producer VARCHAR(20);
ALTER TABLE song ADD CONSTRAINT foreign_key1 FOREIGN KEY(producer) REFERENCES producer;
In MySQL you can use this:
CREATE TABLE producer(
name varchar(20),
PRIMARY KEY (name)
);
CREATE TABLE song(
id int,
name varchar(50) not null,
singer varchar(50) not null,
producer varchar(50) not null,
album varchar(50) not null,
total_sell int not null,
PRIMARY KEY (`id`),
CONSTRAINT `foreign_key1` FOREIGN KEY (`producer`) REFERENCES `producer` (`name`)
);
OR:
ALTER TABLE `song`
ADD CONSTRAINT `foreign_key1`
FOREIGN KEY (`producer`)
REFERENCES `producer` (`name`)
ON DELETE NO ACTION
ON UPDATE NO ACTION;
you can see Here.
I can advise you to declare the same length as the name column. es. varchar(50)
So I tried looking up other questions and tried them, but I was not able to figure out why my SQL was not working. It keeps saying that DepartmentID table does not exist and I have it declared as my primary key under Department.
CREATE TABLE EMPLOYEE(
SSN INT NOT NULL,
WorkID INT NOT NULL,
BirthDate DATE NOT NULL,
Name VARCHAR(20) NOT NULL,
UNIQUE(WorkID),
PRIMARY KEY(SSN),
FOREIGN KEY(DepartmentID) REFERENCES DEPARTMENT(DepartmentID),
FOREIGN KEY(DeviceID) REFERENCES DEVICE(DeviceID)
);
CREATE TABLE DEPARTMENT(
DepartmentID INT NOT NULL,
DepartmentName VARCHAR (20) NOT NULL,
PRIMARY KEY(DepartmentID),
UNIQUE(DepartmentName)
);
CREATE TABLE PRODUCT(
ProductID INT NOT NULL,
Name VARCHAR(20) NOT NULL,
Isle VARCHAR(5) NOT NULL,
Company VARCHAR(20) NOT NULL,
PRIMARY KEY(ProductID),
FOREIGN KEY(DepartmentID) REFERENCES DEPARTMENT(DepartmentID)
);
CREATE TABLE DEVICE(
DeviceID INT NOT NULL,
DateReceived DATE NOT NULL,
PRIMARY KEY(DeviceID)
);
CREATE TABLE SALES(
SalesID INT NOT NULL,
Profit INT NOT NULL,
Revenue INT NOT NULL,
PRIMARY KEY(SalesID)
);
CREATE TABLE AmountSold(
FOREIGN KEY (SalesID) REFERENCES SALES(SalesID),
FOREIGN KEY (ProductID) REFERENCES PRODUCT(ProductID)
);
The problem was that you were making foreign key but the column DepartmentID
doesn't exist on that table in which you were referencing and the second was
that your order wasn't correct.
CREATE TABLE DEPARTMENT(
DepartmentID INT NOT NULL,
DepartmentName VARCHAR (20) NOT NULL,
PRIMARY KEY(DepartmentID),
UNIQUE(DepartmentName)
);
CREATE TABLE DEVICE(
DeviceID INT NOT NULL,
DateReceived DATE NOT NULL,
PRIMARY KEY(DeviceID)
);
CREATE TABLE EMPLOYEE(
SSN INT NOT NULL,
WorkID INT NOT NULL,
BirthDate DATE NOT NULL,
DepartmentID INT NOT NULL,
DeviceID INT NOT NULL,
Name VARCHAR(20) NOT NULL,
UNIQUE(WorkID),
PRIMARY KEY(SSN),
FOREIGN KEY(DepartmentID) REFERENCES DEPARTMENT(DepartmentID),
FOREIGN KEY(DeviceID) REFERENCES DEVICE(DeviceID)
);
CREATE TABLE PRODUCT(
ProductID INT NOT NULL,
Name VARCHAR(20) NOT NULL,
DepartmentID INT NOT NULL,
Isle VARCHAR(5) NOT NULL,
Company VARCHAR(20) NOT NULL,
PRIMARY KEY(ProductID),
FOREIGN KEY(DepartmentID) REFERENCES DEPARTMENT(DepartmentID)
);
CREATE TABLE SALES(
SalesID INT NOT NULL,
Profit INT NOT NULL,
Revenue INT NOT NULL,
PRIMARY KEY(SalesID)
);
CREATE TABLE AmountSold(
FOREIGN KEY (SalesID) REFERENCES SALES(SalesID),
FOREIGN KEY (ProductID) REFERENCES PRODUCT(ProductID)
);
The problem here you didn't declared the DepartmentId column in Employee table. Also execute the parent table first followed by the ones referring
CREATE TABLE DEPARTMENT(
DepartmentID INT NOT NULL,
DepartmentName VARCHAR (20) NOT NULL,
PRIMARY KEY(DepartmentID)
);
CREATE TABLE DEVICE(
DeviceID INT NOT NULL,
DateReceived DATE NOT NULL,
PRIMARY KEY(DeviceID)
);
CREATE TABLE EMPLOYEE(
SSN INT NOT NULL,
WorkID INT NOT NULL,
BirthDate DATE NOT NULL,
Name VARCHAR(20) NOT NULL,
DepartmentID INT,
DeviceID INT ,
UNIQUE(WorkID),
PRIMARY KEY(SSN),
FOREIGN KEY(DepartmentID) REFERENCES DEPARTMENT(DepartmentID),
FOREIGN KEY(DeviceID) REFERENCES DEVICE(DeviceID)
);
CREATE TABLE PRODUCT(
ProductID INT NOT NULL,
Name VARCHAR(20) NOT NULL,
Isle VARCHAR(5) NOT NULL,
Company VARCHAR(20) NOT NULL,
DepartmentID INT,
PRIMARY KEY(ProductID),
FOREIGN KEY(DepartmentID) REFERENCES DEPARTMENT(DepartmentID)
);
CREATE TABLE SALES(
SalesID INT NOT NULL,
Profit INT NOT NULL,
Revenue INT NOT NULL,
PRIMARY KEY(SalesID)
);
CREATE TABLE AmountSold(
SalesId INT NOT NULL,
ProductId INT NOT NULL,
FOREIGN KEY (SalesID) REFERENCES SALES(SalesID),
FOREIGN KEY (ProductID) REFERENCES PRODUCT(ProductID)
);
I know the error 150 is related to foreign keys, but i can't figure out what wrong here.
CREATE TABLE IF NOT EXISTS User(
id_user INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
nom VARCHAR(255) NOT NULL,
prenom VARCHAR(255) NOT NULL,
naissance DATE NOT NULL,
email VARCHAR(255) NOT NULL
);
CREATE TABLE IF NOT EXISTS Livre(
id_livre INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
titre VARCHAR(255) NOT NULL,
parution DATE NOT NULL,
id_edit INT NOT NULL,
id_user INT NOT NULL,
FOREIGN KEY ( id_edit)
REFERENCES Editeur(id_edit)
ON DELETE CASCADE,
FOREIGN KEY ( id_user)
REFERENCES User(id_user)
ON DELETE CASCADE
);
CREATE TABLE IF NOT EXISTS Publication(
id_pub INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
texte TEXT NOT NULL,
date_pub DATE NOT NULL,
titre_pub VARCHAR(255) NOT NULL,
id_livre INT NOT NULL,
id_user INT NOT NULL,
FOREIGN KEY ( id_user)
REFERENCES User(id_user)
ON DELETE CASCADE,
FOREIGN KEY (id_livre)
REFERENCES Livre(id_livre)
ON DELETE CASCADE
);
CREATE TABLE IF NOT EXISTS Editeur(
id_edit INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
nom VARCHAR(255) NOT NULL,
pays VARCHAR(255) NOT NULL,
adresse VARCHAR(255) NOT NULL,
tel VARCHAR(255) NOT NULL
);
The error occurs when i try to create tables Livre and Publication.
Types are the same so it doesn't seem to be the problem.
By mindful of the order in which you create the tables.
For instance, your table creation statement for Livre defines a foreign key on Editeur. But the table Editeur has not been created yet.
Adjust the create table statement ordering as required.