I'm creating a database for my assignment. I had to create 2 tables namely Customer and Job through the "New Query" option in SQL server. After creating both of them, I wanted to add Job_ID (A primary key) from Job table as a foreign key to the Customer table. As I have already created the Customer table, The only option I had was to ALTER the customer table. But after altering, I seemed to get this unusual error.
Msg 1769, Level 16, State 1, Line 1
Foreign key 'Job_ID' references invalid column 'Job_ID' in referencing table 'CUSTOMER'.
Msg 1750, Level 16, State 0, Line 1
Could not create constraint or index. See previous errors.
I can provide you with any more info if necessary.
CREATE TABLE CUSTOMER
(Customer_ID INT NOT NULL PRIMARY KEY,
Customer_Name VARCHAR(15) NOT NULL,
Gender CHAR(1),
Customer_Type VARCHAR(12) NOT NULL,
Addresss VARCHAR(20) NOT NULL,
Telephone_No CHAR(10) NOT NULL);
CREATE TABLE JOB
(Job_ID INT NOT NULL PRIMARY KEY,
Pickup_location VARCHAR (10) NOT NULL,
Destination VARCHAR (10) NOT NULL,
Customer_ID INT FOREIGN KEY REFERENCES CUSTOMER(Customer_ID));
ALTER TABLE CUSTOMER
ADD FOREIGN KEY (Job_ID) REFERENCES JOB(Job_ID);
This looks like the same issue as described here.
When you try to create your foreign key:
ALTER TABLE CUSTOMER
ADD FOREIGN KEY (Job_ID) REFERENCES JOB(Job_ID);
You are saying that you want to use the field Job_ID from the table CUSTOMER:
ALTER TABLE CUSTOMER ADD FOREIGN KEY (Job_ID)
and that the values in this field should match values in the Job_ID column from the table JOB:
REFERENCES JOB(Job_ID);
The problem is that your CUSTOMER table doesn't have a Job_ID column, based on its definition:
CREATE TABLE CUSTOMER
(Customer_ID INT NOT NULL PRIMARY KEY,
Customer_Name VARCHAR(15) NOT NULL,
Gender CHAR(1),
Customer_Type VARCHAR(12) NOT NULL,
Addresss VARCHAR(20) NOT NULL,
Telephone_No CHAR(10) NOT NULL);
The fields in the CUSTOMER table are Customer_ID,Customer_Name,Gender,Customer_Type,Addresss and Telephone_No.
So you either need to add a Job_ID column to the CUSTOMER table, or specify a different field to use in your ALTER TABLE statement - one which does exist in the CUSTOMER table.
More information on ALTER TABLE and ADD FOREIGN KEY specifically can be found here.
I've got a problem to insert some values into table.
Microsoft SQL server management shows that:
The INSERT statement conflicted with the FOREIGN KEY constraint "FK__Players__Menager__55D59338". The conflict occurred in database
"TransferyProjekt", table "dbo.Menagers", column 'idMenager'.
My Create table script.
CREATE TABLE Menagers (
idMenager INT IDENTITY(1,1) NOT NULL,
[name] VARCHAR(30) NOT NULL CHECK (name LIKE '[A-Z]%'),
surname VARCHAR(30) NOT NULL CHECK (surname LIKE '[A-Z]%'),
phoneNumber VARCHAR(18) NOT NULL CHECK (phoneNumber LIKE '+[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'),
PRIMARY KEY (idMenager)
);
CREATE TABLE Players (
idPlayer INT IDENTITY(1,1) NOT NULL,
[name] VARCHAR(30) NOT NULL,
surname VARCHAR(30) NOT NULL,
age DATE NOT NULL check (DATEDIFF(year,age,GETDATE()) > 18),
club INT NOT NULL,
Menager INT NOT NULL,
PRIMARY KEY (idPlayer),
FOREIGN KEY (club) REFERENCES Clubs(idClub),
FOREIGN KEY (Menager) REFERENCES Menagers(idMenager)
);
My insert look like.
INSERT INTO Menagers VALUES
('Adil','Green','+232247832'),
('Wicky','Dock','+301494064'),
('Alead','King','+447499384'),
('Darmian','Dagoly','+445587849'),
('Kamila','Dobra','+958789278'),
('Mateusz','Jankowiak','+849383098'),
('Lendy','Day','+448902920'),
('Martin','Lloyd','+501044468'),
('Adam','Dosh','+045033739'),
('Cristian','Cosy','+307748735'),
('Andrew','Lloyd','+635875452'),
('Matias','Banega','+520091224'),
('Carl','Rossi','+196935415'),
('Michał','Rolnik','+156541588'),
('Denny','Nowsky','+231785387'),
('Micky','Elly','+125774609'),
('George','Taylor','+094371433'),
('Barack','Obama','+916764868'),
('Jin','Chan','+906765545'),
('Lee','Konsu','+608935829'),
('Adam','Kenzo','+417708081'),
('Bryan','Along','+939454178'),
('Robert','Leey','+183354912'),
('Tom','Vardy','+576176145'),
('Kevin','Betword','+721582207');
INSERT INTO Players VALUES
('Lionel','Messi','1986-07-13','23','4'),
('Cristiano','Ronaldo','1986-04-11','23','5'),
('Sergio','Ramos','1986-09-07','23','12'),
('Łukasz','Piszczek','1986-11-20','23','14'),
('Robert','Lewandowski','1986-12-01','2','13'),
('Michał','Pazdan','1986-06-01','3','23'),
('Łukasz','Trałka','1986-05-02','7','20'),
('Łukasz','Teodorczyk','1986-04-14','6','18'),
('Mariusz','Miley','1985-03-06','3','26');
You should define column names if your source table and destination table has different column counts or different order
INSERT INTO Menagers([name],surname, phoneNumber )
VALUES
('Adil','Green','+232247832'),
('Wicky','Dock','+301494064'),
....
INSERT INTO Players([name], surname, age, club, Menager )
VALUES
('Lionel','Messi','1986-07-13','23','4'),
('Cristiano','Ronaldo','1986-04-11','23','5'),
...
Your foreign key and primary key columns are INT type. But, you are having following SQL
INSERT INTO Players VALUES
('Lionel','Messi','1986-07-13','23','4')
where last column belongs to foreign key column and your value is string.
A foreign key is a reference to a unique value in a different table, and SQL will ensure "referential integrity" - which means it won't let you end you with "orphaned" key references. When you insert a value to a foreign key column it must be a null or a existing reference to a row in the other table, and when you delete, you must delete the row containing the foreign key first, then the row it references.
If you don't, you will get an error such as you describe.
So enter the row into the "main" table first, then enter the "dependant" table information second.
In FK column I added unfortunately referece to row who is not exists in table Managers...
('Mariusz','Miley','1985-03-06','3','26');
but I don't have 26'th row in table Managers (Blame me, now) :(
As in my previous post (linked here) I have been designing a table and I'm trying to insert only some specific values into the BrothersName column which can be done by adding a constraint.
TABLE Family
(
BrothersName varchar(30)
);
However my question now is that I'm trying to do this instead by foreign key. Is the only way to do it is by making a new table and add primary key into it?
What can be the best way otherwise?
So you should have a primary key table to hold all possible master data set for brother names like below
create table MasterBrotherNames (ID int IDENTITY(1,1) PRIMARY KEY, Name nvarchar(30)) ;
insert into MasterBrotherNames(Name) values (N'Alex'),(N'Tom');
Now you should hold foreign key ID into the Family table as int, say in column BrothersNameID using following query to create FK relationship
create table Family( BrothersNameID int NOT NULL);
alter table Family add constraint fk_family_brothername foreign key ( BrothersNameID ) references MasterBrotherNames (ID);
To test out try queries below
insert into Family values (1)-- for Alex
insert into Family values (2)-- for Tom
insert into Family values (3)-- this gives error
--The INSERT statement conflicted with the FOREIGN KEY constraint "fk_family_brothername".
Based on OP's following request
is there any way to implement this without having any Id in MasterBrothersName, where only names can be inserted and accepted as values
here's the modified query
create table MasterBrotherNames ( Name nvarchar(30) PRIMARY KEY) ;
insert into MasterBrotherNames(Name) values (N'Alex'),(N'Tom');
create table Family( BrothersName nvarchar(30) NOT NULL);
alter table Family add constraint fk_family_brothername foreign key ( BrothersName ) references MasterBrotherNames (Name);
insert into Family values (N'Alex')-- for Alex
insert into Family values (N'Tom')-- for Tom
insert into Family values (N'A')-- this gives error
--The INSERT statement conflicted with the FOREIGN KEY constraint "fk_family_brothername".
I have created two tables and also created a relationship between them.
Table students:
create table students
(
[StudentId] NVARCHAR(50) NOT NULL PRIMARY KEY,
[Name] NVARCHAR(50) NOT NULL
);
Table studentprofile:
create table studentprofile
(
[Id] INT NOT NULL PRIMARY KEY IDENTITY(1, 1),
[StudentId] NVARCHAR(50) NOT NULL,
[Address] NVARCHAR(50) NOT NULL,
);
and relationship:
alter table studentprofile
add constraint students_studentprofile_FK
foreign key (StudentId)
references students(StudentId)
on delete cascade on update cascade
But, when I wrote this line:
insert into students values('110111', 'Marik')
the value of StudentId (in table studentprofile) wasn't updated automatically. Why?
Can you tell me how to set the value of StudentId (in table studentprofile) can be inserted automatically whenever I insert into table students?
There is no such thing as insert cascade.
You can implement such a thing by using a trigger for insert on your students table, inserting default values (or nulls) into the studentprofile table:
CREATE TRIGGER students_insert ON students AFTER INSERT
AS
INSERT INTO studentprofile(StudentId, Address)
SELECT StudentId, 'NO ADDRESS'
FROM inserted
Note that your Address column is defined as not null and has no default value, this is why I've used the hard coded 'NO ADDRESS' for it.
However, I agree with the comments on your question: you would be better off inserting the data to the student profile using a different insert statement (perhaps inside a transaction with the insert to students).
I'm new to sqlplus and was trying to run a sql script that creates a few tables, but once I try to run it, it gives me an error saying that the table or view doesnt exist and I dont know how to fix this error.
My script is:
drop table Borrower;
create table Borrower (
bid char(100) not null,
password char(100) not null,
name char(100) null,
address char(100) null,
phone char(100) null,
emailAddress char(100) null,
sinOrStNo char(100) null,
expiryDate date null,
--type ENUM('student','faculty','staff'),
type char(100) not null,
--CONSTRAINT Btype_check CHECK (type IN ('student','faculty','staff')),
FOREIGN KEY (type) references BorrowerType(type),
PRIMARY KEY (bid));
grant select on Borrower to public;
"unique/primary keys in table referenced by foreign keys "
Data integrity is crucial to a properly run database so Oracle will not let us drop a table if its primary key is referenced by another table's foreign key. So it hurls ORA-02449.
So, given this set up:
create table t_parent (
id number not null
, constraint tp_pk primary key (id)
);
create table t_child (
id number not null
, p_id number not null
, constraint tc_pk primary key (id)
, constraint tc_tp_fk foreign key (p_id)
references t_parent (id)
);
There are three ways to drop table t_parent.
run drop table t_child first: no child table, no foreign key.
Remove the blocking foreign key: alter table t_child drop constraint tc_pc_fk.
A variant on the previous one, let the database figure out the foreign keys:
drop table t_parent cascade constraints.
The first option is the most proper, because it leaves the database in a valid state (no tables, no possibility of data integrity corruption). The valid use for the third approach is a script which razes all the tables from a schema: it's easy to generate such a script from the data dictionary.
The order that you drop or create tables are important because if you have foreign keys referencing another table, you cant delete that table before deleting your own table.
In this example, the Borrower table has to be dropped before the BorrowerType table.