Common PHP Errors and How to Fix Them
Browse all documented PHP errors with detailed explanations, root causes, and step-by-step fixes.
Notice: Undefined variable: database_connection in /var/www/html/database_operat
This error occurs when a variable has not been declared or initialized before it's being used in a script.…
The controller method 'render' is not defined in the controller 'App\Controllers
This error is thrown when a controller method is not found or is not defined in the controller class.…
Call to undefined method 'render' on a Twig_Template object in /var/www/html/vie
This error occurs when trying to use an undefined or missing method in a framework's templating engine. In this case, th…
Trying to get property 'username' of non-object in /var/www/html/user.php on lin
This error occurs when you're trying to access an object property, but the variable you're accessing is not an object. T…
PDOException: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate en
This error occurs when you attempt to insert a duplicate value into a column that has a unique constraint, such as a pri…
Unexpected '}' at end of file in /var/www/html/script.php on line 1
This error occurs when the PHP interpreter encounters unexpected syntax at the end of a file. In this case, it's a closi…
Undefined variable: user_id in /var/www/html/dashboard.php on line 25
This error occurs when a variable is used before it is declared and assigned a value.…
Notice: Trying to access array offset on value of type null in /var/www/html/pro
This error occurs when you're trying to access a key from an array that doesn't exist or is null. In PHP, you can't dire…
Undefined property: stdClass::$email in /var/www/html/user.php on line 56
This error occurs when a property or method is not defined in an object. It is often caused by typos or incorrect object…
PDOStatement::execute(): SQLSTATE[HY000] [2002] No such file or directory in /va
This error occurs when the PDO database connection fails to connect to the database due to a missing or incorrect file p…
Warning: fclose() expects parameter 1 to be resource, boolean given in /var/www/
This error occurs when a function that expects a resource (such as a file or database connection) is called with a boole…
Warning: Cannot redeclare class Foo in /var/www/html/autoloader.php on line 55
This error occurs when a PHP script attempts to declare a class with the same name in a different scope, usually due to …
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