insert string with single quote(‘) or double quote(“) in mysql

In developing web application, we write insert query for inserting data into database. Hence i use mysql query and PHP functions for inserting string with single quote(‘) or double quote.

let we know two useful PHP function :

1. addslashes – Quote string with slashes. Returns a string with backslashes before characters that need to be quoted in database queries etc. These characters are single quote ('), double quote ("), backslash (\) and NUL (the NULL byte).

<?php
$str = "Is your name O'reilly?";
// Outputs: Is your name O\'reilly?
echo addslashes($str);
?>

2. stripslashes — Un-quote string quoted with addslashes(). Returns a string with backslashes stripped off. (\' becomes ' and so on.) Double backslashes (\\) are made into a single backslash (\).

<?php
$str = "Is your name O\'reilly?";
// Outputs: Is your name O'reilly?
echo stripslashes($str);
?>

Now come to the point…..if we insert string into database with single or double quote like this :

<?php
$str = "Is your name O'reilly?";
$query = "INSERT INTO tbl (description) VALUES ( '$str')";
?>

This will occur error.

but if we use addslashes($str) function like below and then insert into database, then no error will be occurred.

<?php
$str = "Is your name O'reilly?";
$desc_str = addslashes($str);
$query = "INSERT INTO tbl (description) VALUES ( '$desc_str')";
?>

similarly we can use stripslashes($str) to print that table field value like this :

<?php
echo stripslashes($str);
?>

cheers