PHP SQL Variable are denoted with a leading dollar sign ($). The PHP variable includes $ con , $ update and so on.
Understand with Example
This example illustrates how to create the variable in php for sql operation. In this example we create a variable $con for mysql connection and $update. The sign ($) is used to create the variable in php. The code begin with <? php delimiter and end with ?>. The variable $ con is used to assigned the value of mysql_connect ( ) function that accept the parameter local host, user and password. The if loop authenticate the connection between PHP and database. The die script will be executed only if the variable con fail to establish a connection between PHP and database. The variable $ update is used to modify the table emp_table and set the new records for the existing value.
Table: emp_table before insertion
Table: emp_table after insertion
Source Code of sql_variable.php
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