HTTP 500 Internal Server error with PDO

Question

I am getting Internal Server Error when I use the following code. Do I have to change any configuration? I am using PHP version 5.2.6. I couldn't find any documentation about this issue. Please let me know. Thank you.

try {
    $dbh = new PDO($db_host1, $db_username, $db_password);
} catch (PDOException $e) {
    print "Error!: " . $e->getMessage() . "<br/>";
    die();
}

Have you looked in the webserver (presumably apache) error log for what the error is. I've never had php cause a 500 error before. — Philip Couling, Dec 10 '11 at 15:53

score 2 · Answer 1 · answered Dec 10 '11 at 16:34

You have to pass DSN as first parameter of PDO constructor.

try {
    $dsn = "mysql:dbname=testdb;host={$db_host1}";
    $dbh = new PDO($dsn, $db_username, $db_password);
} catch (PDOException $e) {
    print "Error!: " . $e->getMessage() . "<br/>";
    die();
}

score -1 · Answer 2 · edited Mar 31 '22 at 15:50

-1

I had the same 500 error after installing php-mysql.

Solution:

Restart the webserver.

I forgot to restart my webserver, which resolved the problem for me.

Apache error log said :

> PHP Fatal error:  Uncaught Error: Undefined class constant
> 'MYSQL_ATTR_INIT_COMMAND' in /var/www/html/[...].php:8 Stack trace:
> #0 /var/www/html/[...].php(27): myFunction()
> #1 {main}   thrown in /var/www/html/[...].php on line 8, referer: http://localhost/

edited Mar 31 '22 at 15:50

Starsky

1,829
18
25

answered Mar 31 '22 at 14:36

Cari Bou

3
2

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HTTP 500 Internal Server error with PDO

2 Answers2