Creating dynamic tables in HTML using MySQL and PHP

If you want to display the full contents of the database table as an HTML table, I suggest you make a function that will do all of this dynamically for you. This function should check that the table exists, fetch all the data, and fetch output HTML table with headers.

MySQLi solution

Here is my suggestion using MySQLi. First of all, you must make sure that the table actually exists. Then you can fetch all the data from the table. The object returned by mysqli::query() will have all metadata information about column names which you can use to display the header row. You can use fetch_fields() to iterate over each column metadata. The data can be fetched using fetch_all() method.

<?php

// create global connection using mysqli
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$conn = mysqli_connect("localhost", "username", "password", "database", "3306");
$mysqli->set_charset('utf8mb4'); // always set the charset

function outputMySQLToHTMLTable(mysqli $mysqli, string $table)
{
    // Make sure that the table exists in the current database!
    $tableNames = array_column($mysqli->query('SHOW TABLES')->fetch_all(), 0);
    if (!in_array($table, $tableNames, true)) {
        throw new UnexpectedValueException('Unknown table name provided!');
    }
    $res = $mysqli->query('SELECT * FROM '.$table);
    $data = $res->fetch_all(MYSQLI_ASSOC);
    
    echo '<table>';
    // Display table header
    echo '<thead>';
    echo '<tr>';
    foreach ($res->fetch_fields() as $column) {
        echo '<th>'.htmlspecialchars($column->name).'</th>';
    }
    echo '</tr>';
    echo '</thead>';
    // If there is data then display each row
    if ($data) {
        foreach ($data as $row) {
            echo '<tr>';
            foreach ($row as $cell) {
                echo '<td>'.htmlspecialchars($cell).'</td>';
            }
            echo '</tr>';
        }
    } else {
        echo '<tr><td colspan="'.$res->field_count.'">No records in the table!</td></tr>';
    }
    echo '</table>';
}

outputMySQLToHTMLTable($mysqli, 'user');

PDO Solution

Using PDO is very similar but you have to pay attention to the differences in the APIs.

To get the table names, you can use fetchAll(PDO::FETCH_COLUMN) instead of array_column(). To get the column metadata, you need to use getColumnMeta() function.

<?php

$pdo = new PDO("mysql:host=localhost;dbname=test;charset=utf8mb4", 'username', 'password', [
    \PDO::ATTR_ERRMODE => \PDO::ERRMODE_EXCEPTION,
    \PDO::ATTR_EMULATE_PREPARES => false
]);

function outputMySQLToHTMLTable(pdo $pdo, string $table)
{
    // Make sure that the table exists in the current database!
    $tableNames = $pdo->query('SHOW TABLES')->fetchAll(PDO::FETCH_COLUMN);
    if (!in_array($table, $tableNames, true)) {
        throw new UnexpectedValueException('Unknown table name provided!');
    }
    $stmt = $pdo->query('SELECT * FROM '.$table);
    $data = $stmt->fetchAll(PDO::FETCH_ASSOC);
    $columnCount = $stmt->columnCount();
    
    echo '<table>';
    // Display table header
    echo '<thead>';
    echo '<tr>';
    for ($i = 0; $i < $columnCount; $i++) {
        echo '<th>'.htmlspecialchars($stmt->getColumnMeta($i)['name']).'</th>';
    }
    echo '</tr>';
    echo '</thead>';
    // If there is data then display each row
    if ($data) {
        foreach ($data as $row) {
            echo '<tr>';
            foreach ($row as $cell) {
                echo '<td>'.htmlspecialchars($cell).'</td>';
            }
            echo '</tr>';
        }
    } else {
        echo '<tr><td colspan="'.$columnCount.'">No records in the table!</td></tr>';
    }
    echo '</table>';
}

outputMySQLToHTMLTable($pdo, 'user');

P.S. The table existence check can be optimized with the following code instead:

$tableNames = $pdo->prepare('SELECT COUNT(1) FROM information_schema.TABLES WHERE TABLE_SCHEMA = SCHEMA() AND TABLE_NAME=?');
$tableNames->execute([$table]);
if (!$tableNames->fetchColumn()) {
    throw new UnexpectedValueException('Unknown table name provided!');
}