HIOX FREE MySQL Tutorial - Create Tables, Query for Creating a Table using MySQL

Topic

How to create a table?

Explanation

Creating tables :

    Once you have selected the database, we can start creating tables. The CREATE statement is used to create a table in MySQL with constraint. A Constraint is restriction to the behavior of a variable.

The Create syntax is

CREATE TABLE tableName
(
    fieldName1 dataType(size) [NULL | NOT NULL]
    fieldName2 dataType(size) [NULL | NOT NULL]
);

    If NULL is specified, the field is allowed to be left empty. If NOT NULL is specified, the field must be given a value. In the absence of either a NULL or NOT NULL, NULL is assumed.

    The below example query will help you in creating table:

CREATE TABLE student
(
    studID INT(5),
    name VARCHAR(30),
);

    The above query will create the table student with fields ID and Name.

PRIMARY KEY :

    A PRIMARY KEY is a field in a table that uniquely identifies a record. This attribute is used to define the field name to create a primary key.

Example :

    fieldName INT UNSIGNED AUTO_INCREMENT PRIMARY KEY

    The PRIMARY KEY is specified after defining the fields in the below example:

CREATE TABLE student
(
    studID INT UNSIGNED AUTO_INCREMENT,
    name VARCHAR(30),
    PRIMARY KEY(studID)
);

    We can also create a compound primary key. A compound primary key is where more than one field is used to uniquely identify a record.

    Lets create a table for holding student details in a class.

mysql> create table student(studid int(10), name varchar(20), address varchar(40), phone int(10));
Query OK, 0 rows affected (0.05 sec)