Why Can\'t My PHP Code Find a Database That Exists in PHPMyAdmin?

Troubleshooting Database Connectivity Issues in PHP

Connecting to a MySQL database using PHP can sometimes present challenges when dealing with newly created databases. This article explores a common error encountered when PDO is used to connect to a database that exists in PHPMyAdmin but not in PHP.

To understand the root cause, it's crucial to consider two possibilities:

1. Spelling Errors: Verify the database name in your PHP code and PHPMyAdmin to eliminate any potential spelling mistakes.
2. Mismatched Database Servers: It's possible that PHPMyAdmin and PHP are accessing different database servers. To confirm this, execute the following query in PHPMyAdmin:

<code class="sql">show databases;</code>

Then, run the same query in PHP using either PDO or mysqli:

For PDO:

<code class="php">$host = 'your db host';
$user = 'your db username';
$pass = 'your db password';

$pdo = new PDO("mysql:host=$host", $user, $pass, [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION]);
$databases = $pdo->query('show databases')->fetchAll(PDO::FETCH_COLUMN);
var_dump($databases);</code>

For mysqli:

<code class="php">$host = 'your db host';
$user = 'your db username';
$pass = 'your db password';

mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$mysqli = mysqli_connect($host, $user, $pass);
$databases = $mysqli->query('show databases')->fetch_all();
var_dump($databases);</code>

Compare the outputs to determine if there are any discrepancies. If the databases are different, the issue lies with the server configuration.

To resolve the server misconfiguration issue, inspect PHPMyAdmin's configuration file to ensure it specifies the correct server.

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