Common PHP Errors and How to Fix Them
Browse all documented PHP errors with detailed explanations, root causes, and step-by-step fixes.
Call to undefined method Laravel\Support\Str::slug()
This error occurs when you're trying to use a method or function that doesn't exist in a specific class or object, in th…
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…
Missing required parameter 'csrf_token' in /var/www/html/user.php on line 55
The CSRF (Cross-Site Request Forgery) token is a security measure to prevent malicious requests. This error occurs when …
Cannot send headers. Output started at /var/www/html/index.php:123
This error occurs when PHP tries to send HTTP headers after the output has already started. In PHP, headers must be sent…
Notice: Undefined variable: cart in /var/www/html/cart.php on line 67
This error occurs when a script tries to use a variable that hasn't been declared or initialized yet.…
SQLSTATE[HY000][1049] Unknown database 'my_database' (SQL: select * from users w
This error occurs when the database connection fails due to an unknown or non-existent database. This can happen when th…
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…
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…
The route resource function must be defined within a route group or namespace in
This error occurs when attempting to define a resource route outside of a route group or namespace in Laravel 9. It's a …
syntax error, unexpected 'if' (T_IF), expecting ',' or ';' on line 10
This error occurs when PHP encounters a syntax that is not allowed in the current context. In this case, the 'if' statem…
Fatal error: Uncaught PDOException: SQLSTATE[HY093]: Invalid parameter number: p
This error occurs when PDO (PHP Data Objects) encounters an invalid parameter in a prepared statement. The parameter is …
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