PHP Content Filter: Replace Bad Words

CREATE TABLE `filter` (
  `word` varchar(50) NOT NULL,
  PRIMARY KEY (`word`)
) ENGINE=MyISAM;

<?php
 
// Create a global connection variable
$connection = new mysqli("localhost", "username", "password", "database"); // Replace with your DB credentials
 
// Check for connection errors
if ($connection->connect_error) {
    die("Database connection failed: " . $connection->connect_error);
}
 
// Create a function to filter bad words
function filter($content) {
    global $connection; // Access the global connection variable
 
    // Prepare and execute the query to fetch all words from the `filter` table
    $query = "SELECT word FROM filter";
    $result = $connection->query($query);
 
    // Check if the query returned any rows
    if ($result->num_rows > 0) {
        // Loop through the rows and replace bad words with "(BadWord)"
        while ($row = $result->fetch_assoc()) {
            $content = str_replace($row['word'], "(BadWord)", $content);
        }
    }
 
    // Free the result set
    $result->free();
 
    // Return the "safe" content
    return $content;
}
 
// Close the database connection
$connection->close();
?>

include("filter.php");

// Example usage
$content = "This is a example text."; // Example content
echo filter($content); // Apply the filter function
 
// Output (if "example" is in the table as a "bad word"
// This is a (BadWord) text.