AUTO_INCREMENT means that the column will automatically get the value. To illustrate this, we create a table called "employees" as shown below:
mysql> Show Create Table employees\G *************************** 1. row *************************** Table: employees Create Table: CREATE TABLE `employees` ( `Id` int(11) NOT NULL AUTO_INCREMENT, `Name` varchar(35) DEFAULT NULL, PRIMARY KEY (`Id`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 1 row in set (0.00 sec)
From the above result set, we can see that the id column has been given the auto-increment option. Now when we insert a value in the Name field, the id field will automatically get the value −
mysql> Insert Into employees(Name) Values('Ram'); Query OK, 1 row affected (0.09 sec) mysql> Insert Into employees(Name) Values('Shyam'); Query OK, 1 row affected (0.03 sec) mysql> Insert Into employees(Name) Values('Mohan'); Query OK, 1 row affected (0.04 sec) mysql> Insert Into employees(Name) Values('Sohan'); Query OK, 1 row affected (0.04 sec) mysql> Select * from employees; +----+-------+ | Id | Name | +----+-------+ | 1 | Ram | | 2 | Shyam | | 3 | Mohan | | 4 | Sohan | +----+-------+ 4 rows in set (0.00 sec)
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