Foreign keys

CREATE TABLE Employee(
    EmployeeID int NOT NULL,
    LastName varchar(50) NOT NULL,
    FirstName varchar(20) NOT NULL,
    Age int,
    DeptNo int,
    PRIMARY KEY (EmployeeID),
    FOREIGN KEY (DeptNo) REFERENCES Department(DeptNo)
);

Foreign key

USE Organization
CREATE TABLE Employee_Office
(
Id INT PRIMARY KEY IDENTITY(1,1),
Emp_Id int FOREIGN KEY REFERENCES Employee(Id),
Office_Id int FOREIGN KEY REFERENCES Office(Id)
)

Source: codingsight.com

What is foreign key

Foreign Key: 
It is a column that comes from a different table and
using Foreign key tables are related each other
It is the primary key of another table
It can be duplicate or null for another table

Foreign key

CREATE TABLE Employee(
    EmployeeID int NOT NULL,
    LastName varchar(50) NOT NULL,
    FirstName varchar(20) NOT NULL,
    Age int,
    DeptNo int,
    PRIMARY KEY (EmployeeID),
    FOREIGN KEY (DeptNo) REFERENCES Department(DeptNo)
);

Source: computerscienceai.com

Foreign key

USE Organization
CREATE TABLE Employee
(
Id INT PRIMARY KEY IDENTITY(1,1),
Name VARCHAR (50) NOT NULL,
Age INT,
Gender VARCHAR (50),
Dep_Id int FOREIGN KEY REFERENCES Department(Id),
Insur_Id int FOREIGN KEY REFERENCES Insurance(Id)
)

Source: codingsight.com

Similar codes

0 vote149 views1 answer
Sqlite3 get data from table c
SQL
0 vote142 views10 answers
Sql statement checker corrector
SQL
0 vote154 views1 answer
Get the Db column names from a SqlDataReader
SQL
0 vote161 views1 answer
Dual in db2
SQL
1 vote155 views1 answer
Sqlite3 read only
SQL
23 votes151 views3 answers
Sql where contains part of string
SQL
1 vote153 views2 answers
Foreign key set 0
SQL
0 vote107 views1 answer
Mysql collation for all languages
SQL
5 votes100 views1 answer
Copy table from one database to another mysql
SQL
3 votes153 views1 answer
Oracle get trigger ddl
SQL