How can the issue of "Undefined index" be resolved when accessing values from a database query in PHP?

When accessing values from a database query in PHP, the "Undefined index" issue occurs when trying to access an array key that does not exist. To resolve this, you should first check if the key exists in the array before trying to access it. This can be done using the isset() function to avoid the error and handle it appropriately. 

// Check if the key exists before accessing it
if(isset($row['key'])) {
    // Access the value if the key exists
    $value = $row['key'];
} else {
    // Handle the case where the key is undefined
    $value = "N/A";
}

Keywords

PHP Undefined index Database query Error handling Array indexing

Related Questions