Find duplicate content using MySQL and PHP

<?php

// Establish a connection to the MySQL database
$conn = mysqli_connect("localhost", "username", "password", "database_name");

// Query the database to fetch all records from the content_table
$sql = "SELECT * FROM content_table";
$result = mysqli_query($conn, $sql);

// Loop through the records and store the content in an array
$content_array = array();
while ($row = mysqli_fetch_assoc($result)) {
    $content_array[] = $row['content'];
}

// Close the database connection
mysqli_close($conn);

?>

<?php

// Loop through the content array and count the number of occurrences of each item
$occurrences = array_count_values($content_array);

// Loop through the occurrences array and output the duplicates
foreach ($occurrences as $key => $value) {
    if ($value > 1) {
        echo "Duplicate content: " . $key . "<br>";
    }
}

?>