"employee" table has E_ID, E_Name, E_Address, E_Mail, E_Dept. [E_ID is primary key]
"salary" table has E_ID, S_Amount, S_Date columns.
In Salary table , add a new column say 'id' set it as integer , primary key , auto-increment.
Do not make E_ID as primary column in Salary table. As you have defined it as a primary key , you can only able to insert it once. Primary key is a unique key table and does not repeated.
You may use this script
CREATE TABLE IF NOT EXISTS `salary` ( `id` int(10) NOT NULL AUTO_INCREMENT, `E_ID` int(11) NOT NULL, `S_Amount` decimal(10,2) NOT NULL, `S_Date` datetime NOT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=1 ;
Here S_Amount column is Decimal type as it is used to store salary. You can use integer also