PHP How to deleting data from MySQL database

Data can be deleted from MySQL tables by executing SQL DELETE statement through PHP function mysql_query.
Below is a simple example to delete records into employee table. To delete a record in any table it is required to locate that record by using a conditional clause. Below example uses primary key to match a record in employee table.

Example:

Try out following example to understand delete operation. You need to provide an employee ID to delete an employee record from employee table.
<html>
<head>
<title>Delete a Record from MySQL Database</title>
</head>
<body>

<?php
if(isset($_POST['delete']))
{
$dbhost = 'localhost:3036';
$dbuser = 'root';
$dbpass = 'rootpassword';
$conn = mysql_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
  die('Could not connect: ' . mysql_error());
}

$emp_id = $_POST['emp_id'];

$sql = "DELETE employee ".
       "WHERE emp_id = $emp_id" ;

mysql_select_db('test_db');
$retval = mysql_query( $sql, $conn );
if(! $retval )
{
  die('Could not delete data: ' . mysql_error());
}
echo "Deleted data successfully\n";
mysql_close($conn);
}
else
{
?>
<form method="post" action="<?php $_PHP_SELF ?>">
<table width="400" border="0" cellspacing="1" cellpadding="2">
<tr>
<td width="100">Employee ID</td>
<td><input name="emp_id" type="text" id="emp_id"></td>
</tr>
<tr>
<td width="100"> </td>
<td> </td>
</tr>
<tr>
<td width="100"> </td>
<td>
<input name="delete" type="submit" id="delete" value="Delete">
</td>
</tr>
</table>
</form>
<?php
}
?>
</body>
</html>

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