Why Are My mysql_* Functions Not Working After Upgrading to PHP 5.5.0?
Difficulty Using mysql_* Functions after PHP Upgrade
Users upgrading to PHP 5.5.0 may encounter issues when attempting to utilize mysql_* functions, as these functions have been deprecated in this version.
Understanding the Issue
One of the common errors encountered is "Deprecated: mysql_real_escape_string()". This indicates that the mysql_real_escape_string() function is no longer supported. Attempting to replace it with mysqli_real_escape_string() results in another error, "Warning: mysqli_real_escape_string() expects exactly 2 parameters, 1 given".
Resolving the Problem
To resolve this issue, it is recommended to transition to using the mysqli extension instead of the mysql extension. This requires updates to your PHP code to utilize mysqli functions.
Revised PHP Code
Here is a revised version of the code provided as an example:
<code class="php"><?php require_once("includes/session.php"); require_once("connections/connection.php"); require_once("includes/functions.php"); // ... (remainder of the PHP code) $connection = mysqli_connect("host", "my_user", "my_password", "my_db"); // ... (remainder of the PHP code) $username = mysqli_real_escape_string($connection, $username); $password = mysqli_real_escape_string($connection, $password); // ... (remainder of the PHP code) // ... (mysqli alternative not shown in detail) if (isset($connection)) { mysqli_close($connection); } ?></code>
Conclusion
Upgrading to PHP 5.5.0 requires compatibility adjustments in existing PHP code. Transitioning to the mysqli extension and utilizing its functions is an effective solution for resolving issues related to deprecated mysql_* functions.
The above is the detailed content of Why Are My mysql_* Functions Not Working After Upgrading to PHP 5.5.0?. For more information, please follow other related articles on the PHP Chinese website!

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