Create table test1
(
id bigint Not Null,
name varchar(10) Not Null
constraint pk_test primary key(id,name)
)
Create table test2
(
Mid bigint Not Null references test1(id) ,
MSalary varchar(10) Not Null
)
In test2 I am not able to create a reference to test1 id Please help me..
Thanks in Advance!!!!
You need a foreign key in order to reference a table. Try this:
CREATE TABLE test1
(
id bigint NOT NULL PRIMARY KEY,
name varchat(10) NOT NULL
)
CREATE TABLE test2
(
Mid bigint NOT NULL,
MSalary varchar(10) NOT NULL,
FOREIGN KEY (Mid) REFERENCES test1(id)
)
Related
This is an assignment and I have been given this diagram for reference - https://imgur.com/gallery/wRkArmQ
There are other tables that I will include but the issue seems to be with the tables section and time_slot. In the diagram, they reference each other but I don't know how to. Any comments are helpful! I am using Oracle btw, here is the code -
create table department (
dept_name varchar(15) primary key,
building varchar(10),
budget int
);
create table instructor (
id varchar(10) primary key,
name varchar(15) not null,
dept_name varchar(20) not null
references department(dept_name) on delete cascade,
salary int not null
);
create table course (
course_id varchar(10) primary key,
title varchar(10),
dept_name varchar(15)
references department(dept_name) on delete cascade,
credits int
);
create table classroom (
building varchar(10) not null,
room_no varchar(5) not null,
capacity int not null,
primary key (building, room_no)
);
create table section (
course_id varchar(10) not null
references course(course_id),
sec_id varchar(10) not null,
semester varchar(10) not null,
year varchar(10) not null,
building varchar(10) not null
references classroom(building),
room_no varchar(5) not null
references classroom(room_no),
time_slot_id varchar(5) not null
references time_slot(time_slot_id),
primary key (course_id, sec_id, semester, year)
);
create table time_slot (
time_slot_id varchar(5) not null
references section(time_slot_id),
day varchar(10) not null,
start_time date not null,
end_time date not null,
primary key (time_slot_id, day, start_time)
);
create table teaches (
id varchar(10) primary key
references instructor(id) on delete cascade,
course_id varchar(15) not null
references section(course_id),
sec_id varchar(5) not null
references section(sec_id),
semester varchar(15)
references section(semester),
year int not null
references section(year)
);
create table student (
id varchar(10) not null primary key,
name varchar(20) not null,
dept_name varchar(15) not null
references department(dept_name) on delete cascade,
tot_cred int not null
);
create table advisor (
s_id varchar(10) primary key
references student(id) on delete cascade,
i_id varchar(6)
references instructor(id) on delete cascade
);
create table prereq (
course_id varchar(10)
references course(course_id) on delete cascade,
prereq_id varchar(10)
references course(course_id) on delete cascade,
primary key (course_id, prereq_id)
);
create table takes (
id varchar(10) not null
references student(id) on delete cascade,
course_id varchar(10) not null
references section(course_id) on delete cascade,
sec_id varchar(10) not null
references section(sec_id) on delete cascade,
semester varchar(10) not null
references section(semester) on delete cascade,
year int not null
references section(year) on delete cascade,
grade varchar(10) not null,
primary key (id, course_id, sec_id, semester, year, grade)
);
This is the output -
Table created.
Table created.
Table created.
Table created.
ORA-02270: no matching unique or primary key for this column-list
ORA-00942: table or view does not exist
ORA-00942: table or view does not exist
The ArtistID column in Piece table refers to the ArtistID in the Artist table. Likewise, the LocationID column in Piece refers to LocationID in the GeographicLocation table. However, both foreign key references throw a "not the same data type as referencing column" error. What am I doing wrong?
CREATE TABLE dbo.Artist
(
ArtistID SMALLINT PRIMARY KEY IDENTITY,
LastName VARCHAR(50) NOT NULL,
FirstName VARCHAR(40) NOT NULL,
Nationality VARCHAR(10) NULL,
BirthYear SMALLINT NOT NULL CHECK(BirthYear <= 1980),
DeathYear SMALLINT NULL,
Sex CHAR(1) NOT NULL CHECK(Sex = 'F' OR Sex = 'M')
)
CREATE TABLE dbo.Piece
(
PieceID SMALLINT PRIMARY KEY IDENTITY(1, 5),
ArtistID SMALLINT NOT NULL
FOREIGN KEY REFERENCES Artist(ArtistID),
LocationID SMALLINT NOT NULL
FOREIGN KEY REFERENCES GeographicLocation(LocationID),
CommonName VARCHAR(100) NULL,
YearProduced TINYINT NULL,
Period VARCHAR(50) NULL,
Medium VARCHAR(35) NOT NULL,
Frame VARCHAR(35) NULL,
AppraisedValue MONEY NOT NULL,
AppraiserID SMALLINT NOT NULL
FOREIGN KEY REFERENCES Appraiser(AppraiserID)
)
CREATE TABLE dbo.GeographicLocation
(
LocationID SMALLINT PRIMARY KEY IDENTITY,
Country VARCHAR(25) NOT NULL,
City VARCHAR(50) NOT NULL
)
I think you missed a table here, which is AppraiserID column in Piece table refers to the AppraiserID in the Appraisertable
So, when I execute your SQL I am getting below error:
Foreign key 'FK__Piece__Appraiser__322C6448' references invalid table 'Appraiser'.
First Create a table called Appraiser, then create Foreign key references for those column.
Below SQL I am able to create all tables and Foreign key references:
CREATE TABLE dbo.Artist
(ArtistID SMALLINT PRIMARY KEY IDENTITY,
LastName VARCHAR(50) NOT NULL,
FirstName VARCHAR(40) NOT NULL,
Nationality VARCHAR(10) NULL,
BirthYear SMALLINT NOT NULL CHECK(BirthYear <= 1980),
DeathYear SMALLINT NULL,
Gender CHAR(1) NOT NULL CHECK(Gender = 'F' OR Gender = 'M'))
CREATE TABLE dbo.GeographicLocation
(LocationID SMALLINT PRIMARY KEY IDENTITY,
Country VARCHAR(25) NOT NULL,
City VARCHAR(50) NOT NULL)
CREATE TABLE dbo.Appraiser
(AppraiserID SMALLINT PRIMARY KEY IDENTITY(1, 5),
AppraisedValue MONEY NOT NULL,
AppraisedName VARCHAR(100) NULL)
CREATE TABLE dbo.Piece
(PieceID SMALLINT PRIMARY KEY IDENTITY(1, 5),
ArtistID SMALLINT NOT NULL,
LocationID SMALLINT NOT NULL,
CommonName VARCHAR(100) NULL,
YearProduced TINYINT NULL,
Period VARCHAR(50) NULL,
Medium VARCHAR(35) NOT NULL,
Frame VARCHAR(35) NULL,
AppraisedValue MONEY NOT NULL,
AppraiserID SMALLINT NOT NULL)
ALTER TABLE dbo.Piece WITH CHECK ADD CONSTRAINT FK_Piece_ArtistID FOREIGN KEY(ArtistID)
REFERENCES dbo.Artist (ArtistID)
GO
ALTER TABLE dbo.Piece CHECK CONSTRAINT FK_Piece_ArtistID
GO
ALTER TABLE dbo.Piece WITH CHECK ADD CONSTRAINT FK_Piece_AppraiserID FOREIGN KEY(AppraiserID)
REFERENCES dbo.Appraiser (AppraiserID)
GO
ALTER TABLE dbo.Piece CHECK CONSTRAINT FK_Piece_AppraiserID
GO
ALTER TABLE dbo.Piece WITH CHECK ADD CONSTRAINT FK_Piece_LocationID FOREIGN KEY(LocationID)
REFERENCES dbo.GeographicLocation (LocationID)
GO
ALTER TABLE dbo.Piece CHECK CONSTRAINT FK_Piece_LocationID
GO
When I have table with PRIMARY KEY from 2 columns:
CREATE TABLE SizeTypes
(
TypeID tinyint NOT NULL,
SizeID tinyint NOT NULL,
Name varchar(100) NOT NULL,
CONSTRAINT PK_SizeType
PRIMARY KEY (TypeID, SizeID)
)
How can I create second table with a foreign key that have 1st constant value and 2nd from column like below:
CREATE TABLE Something
(
ID INT IDENTITY(1,1) PRIMARY KEY,
SizeTypeID_1 TINYINT,
SizeTypeID_2 TINYINT,
SizeTypeID_3 TINYINT,
CONSTRAINT FK_Something_SizeTypes_1
FOREIGN KEY (1, SizeTypeID_1)
REFERENCES SizeTypes(TypeID, SizeID),
CONSTRAINT FK_Something_SizeTypes_2
FOREIGN KEY (2, SizeTypeID_2)
REFERENCES SizeTypes(TypeID, SizeID),
CONSTRAINT FK_Something_SizeTypes_3
FOREIGN KEY (3, SizeTypeID_3)
REFERENCES SizeTypes(TypeID, SizeID)
)
This can be done using FOREIGN KEY, if yes then how?
If no then what other ways to do this I have? Triggers on INSERT and UPDATE for table something and on DELETE for table SizeTypes? Any other choices I have?
It looks like the following code will let you create suitable check constraints with the check implemented by a separate function:
-- Create the first table.
create table SizeTypes(
TypeId TinyInt not NULL,
SizeId TinyInt not NULL,
Name VarChar(100) not NULL,
constraint PK_SizeType primary key ( TypeId, SizeId ) );
go
-- Create a function to implement the logic for the check constraint.
create function CheckSizeTypeId(
#TypeId TinyInt, #SizeId TinyInt )
returns Int
as begin
-- Replace the following statement with the logic for your check.
if #SizeId >= 0 and #SizeId <= ( select SizeId from SizeTypes where TypeID = #TypeID )
return 1;
return 0;
end;
go
-- Create the second table with the check constraints.
create table Something(
Id Int identity(1,1) primary key,
SizeTypeId_1 TinyInt,
SizeTypeId_2 TinyInt,
SizeTypeId_3 TinyInt,
constraint Check_SizeTypeId_1 check ( dbo.CheckSizeTypeId( 1, SizeTypeId_1 ) = 1 ),
constraint Check_SizeTypeId_2 check ( dbo.CheckSizeTypeId( 2, SizeTypeId_2 ) = 1 ),
constraint Check_SizeTypeId_3 check ( dbo.CheckSizeTypeId( 3, SizeTypeId_3 ) = 1 ) );
go
-- Houseclean.
drop table SizeTypes;
drop table Something;
drop function CheckSizeTypeId;
Note that the constraints restrict what you can do with values in Something. Changes in SizeTypes will not revalidate data in Something, though that could be implemented in a trigger on SizeTypes.
I am making a database which links together two tables via the primary key of the first table. The one with the primary key which links the two is created first but how do i make the second record get the ID of the record I just created?
create table Person
(
Person_ID int IDENTITY(100000,1) primary key,
First_Name varchar(20) not null,
Last_Name varchar(20) not null,
)
create table Employee
(
Employee_ID int identity(100000,1) primary key,
Person_ID int references Person(Person_ID),
Employee_Type varchar(10)
)
insert into Person(First_Name, Last_Name) values ('Michael', 'Chu');
insert into Employee(Person_ID, Employee_Type,) values (????????, 'Admin');
I've had a look at the 'last()' function but not really sure how to utilise that. Other then that, I have no idea. Can someone help me out or guide me in the right direction.
try this:
create table Person
(
Person_ID int IDENTITY(100000,1) primary key,
First_Name varchar(20) not null,
Last_Name varchar(20) not null,
)
create table Employee
(
Employee_ID int identity(100000,1) primary key,
Person_ID int references Person(Person_ID),
Employee_Type varchar(10)
)
DECLARE #myID AS INT
insert into Person(First_Name, Last_Name) values ('Michael', 'Chu');
SET #myID = ##IDENTITY
insert into Employee(Person_ID, Employee_Type,) values (#myID , 'Admin');
The following is a contrived simplified example:
USE Test;
IF OBJECT_ID('dbo.Books', 'U') IS NOT NULL
DROP TABLE dbo.Books;
IF OBJECT_ID('dbo.Authors', 'U') IS NOT NULL
DROP TABLE dbo.Authors;
CREATE TABLE dbo.Authors
(
AuthorId BIGINT NOT NULL PRIMARY KEY IDENTITY(1,1),
AuthorName NVARCHAR(MAX) NOT NULL
)
CREATE TABLE dbo.Books
(
BookId BIGINT NOT NULL PRIMARY KEY IDENTITY(1,1),
BookTitle NVARCHAR(MAX) NOT NULL,
FirstAuthorId BIGINT NOT NULL,
CONSTRAINT [FK_BookToFirstAuthor_Authors] FOREIGN KEY([FirstAuthorId]) REFERENCES Authors([AuthorId])
)
Would this be an efficient enough structure to full text search (e.g. via CONTAINS) in BookTitle and (First)AuthorName?
Or would something like this be better:
CREATE TABLE Books
(
BookId BIGINT NOT NULL PRIMARY KEY IDENTITY(1,1),
BookTitle NVARCHAR(MAX) NOT NULL,
FirstAuthorId BIGINT NOT NULL,
FirstAuthorName NVARCHAR(MAX) NOT NULL,
CONSTRAINT [FK_BookToFirstAuthor_Authors] FOREIGN KEY([FirstAuthorId]) REFERENCES Authors([AuthorId])
)
Please note that I see Book rows like immutable 'objects'. Any feedback would be very much appreciated. Many thanks.