What is PHP MySQL N escaped string

When using PHP and MySQL, you often need to process string data. However, this data may contain special characters such as slashes, quotation marks, backslashes, etc. These special characters may cause queries, inserts, updates and other operations to fail, or even cause security vulnerabilities. In order to avoid these situations, we need to escape these special characters to ensure the security and correctness of the data.

So, what is the MySQL N escape string in PHP?

In PHP, MySQL N-escape string is a function used to process string data. This function uses MySQL's N-escape algorithm to escape special characters in a string into a format that can be safely stored in the database. Using this function can avoid problems such as SQL injection attacks and data loss.

The MySQL N escape string function in PHP is mysql_real_escape_string(). The prototype of this function is:

string mysql_real_escape_string (string $unescaped_string [, resource $link_identifier])

Among them, $unescaped_string represents the string to be escaped, and $link_identifier represents the MySQL connection identifier. Optional parameters.

How to use MySQL N to escape a string?

Using MySQL N to escape strings is very simple. Just pass the string to be escaped as the first parameter of mysql_real_escape_string().

For example, we have the following code:

$unescaped_string = "It's a nice day!";
$escaped_string = mysql_real_escape_string($unescaped_string);

In this In this example, we want to escape the string "It's a nice day!" into a format that can be safely stored. We pass this string as the first parameter of mysql_real_escape_string() and get the escaped string $escaped_string. Finally, we store $escaped_string in the database to ensure the safety and correctness of the data.

It should be noted that the mysql_real_escape_string() function can only be used to process string type data. If you want to process other types of data such as integer and floating point, you need to use other conversion functions.

Summary

In PHP, MySQL N-escape string is a function used to process string data. This function uses MySQL's N-escape algorithm to escape special characters in a string into a format that can be safely stored in the database. Proper use of MySQL N-escape strings can avoid SQL injection attacks, data loss and other problems, and ensure the security and correctness of data.

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