Question

In my MySQL table, I have a column of TEXT type. On my HTML Form, user pastes text into it that might contain “” , ‘ ( ) and so on. I want to know how to safely execute Insert Query if these characters exist in the text and might crash the query execution.

How to handle them properly in PHP?

Answer 1

Use a prepared statement.

Prepared statements can help increase
security by separating SQL logic from
the data being supplied. This
separation of logic and data can help
prevent a very common type of
vulnerability called an SQL injection
attack. Normally when you are dealing
with an ad hoc query, you need to be
very careful when handling the data
that you received from the user. This
entails using functions that escape
all of the necessary trouble
characters, such as the single quote,
double quote, and backslash
characters. This is unnecessary when
dealing with prepared statements. The
separation of the data allows MySQL to
automatically take into account these
characters and they do not need to be
escaped using any special function.

A quick example,

$db = new mysqli('localhost', 'username', 'password', 'db');
$stmt = $db->prepare("INSERT INTO mytable (text_column) VALUES (?)");
$stmt->bind_param("s", $mytext); // s = string, b = boolean, i = int, etc
$stmt->execute();
...