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Next, we give an example of a statement that creates an EMPLOYEE table with the following attributes: ID, FName,
        LName, Gender, Address, City, Pin_Code, DOB, Salary and DeptNo. Also note that attribute ID is the
        primary key of the table EMPLOYEE. When the primary key comprises a single attribute, often we use the keyword
        PRIMARY KEY, following the type of the attribute to denote that it is the primary key of the table as shown below
        in the CREATE TABLE statement:
        CREATE TABLE: Used to specify

        Table name
        Attribute names, default values
        Attribute types
        Primary key

        Constraints: NOT NULL, foreign key, values allowed



        CREATE TABLE EMPLOYEE (
        ID INT PRIMARY KEY,
        FName VARCHAR(20) NOT NULL,
        LName VARCHAR(20) NOT NULL,
        Gender CHAR(1) NOT NULL,

        Address VARCHAR(30),
        City VARCHAR(20),
        Pin_Code CHAR(6),
        DOB DATE,

        Salary INT NOT NULL,
        Dept_No SMALLINT
        ); #EMPLOYEE


        The primary key can also be specified after all attributes have been defined, as shown in the CREATE TABLE statement  below:

        CREATE TABLE EMPLOYEE (
        ID INT NOT NULL UNIQUE,
        FName VARCHAR(20) NOT NULL,
        LName VARCHAR(20) NOT NULL,
        Gender CHAR(1) NOT NULL,
        Address VARCHAR(30),
        City VARCHAR(20),
        Pin_Code CHAR(6),
        DOB DATE,
        Salary INT NOT NULL,
        Dept_No SMALLINT,
        PRIMARY KEY(ID)

        ); #EMPLOYEE
        As  ID  is  the  primary  key  for  the  table  EMPLOYEE, no two employees  can  have the same  ID,i.e.,  ID must be
        unique across the EMPLOYEE table. Further, as ID identifies an employee uniquely, this attribute cannot be NULL.
        So, column constraints UNIQUE and NOT NULL are automatically applied to the attribute ID.

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