Question

Write the query string that will delete the user record from the "user" table having user_nameequal to the string value stored in variable $username.

Answer 1

Write the query string that will delete the user record from the "user" table having user_nameequal to the string value stored in variable $username.

MySql Query using PHP:

$query=mysql_query("DELETE FROM user WHERE user_name='%s'",mysql_real_escape_string($username)); // using mysql_query

Syntax:
   mixed mysql_query(string query,sql_connection);

using mysql_query() function executes a query on a MySql database
mysql_real_escape_string() function is used to escapes special characters in a string for use in an sql statement

Example in PHP Code:

<?php

$con=mysql_connect("localhost","user","password"); // create database connection with $con object

if (!$con) // check connection is failed
{
die('Connection Failed...'.mysql_error()); // exit from database
}

$_username=mysql_real_escape_string($username); // escape special characters in a string in $username
$query="DELETE FROM user WHERE user_name='$_username'"; // create a query with query object $query
mysql_select_db('test_db'); // set the current active database
$uname=mysql_query($query,$con); // using mysql_query() function execute query and assign $username variable
if ($uname) //check $username exist then,
{
echo "Record is Successfully Deleted...."; // display this message
}
else
{
echo "Record is not avaialable" .mysql_error(); // else, display this message
}
?>