PHP $db PDO connection error

Question

I wanted to make posts and comments system.
Posts worked fine, but comments had

PHP error: Fatal error: Uncaught exception 'PDOException' with message 'invalid data source name' in C:\xampp\htdocs\index.php:133 Stack trace: #0 C:\xampp\htdocs\index.php(133): PDO->__construct('localhost', 'root', '') #1 {main} thrown in C:\xampp\htdocs\index.php on line 133. `

$db = new PDO ("localhost", "root", "");
$query = $db->prepare("SELECT * FROM comments");
$query->execute();
while($fetch = $query->fetch(PDO::FETCH_ASSOC)){
    $name = $fetch['name'];
    $message = $fetch['comment'];
    echo "<li class='com'><b>".ucwords($name)."</b> - ".$message."</li>";
}

It's element of table. Please help.

For now, you haven't selected a database. php.net/manual/en/pdo.construct.php — sinaza
– sinaza, Commented Jan 11, 2016 at 10:40
Please edit the code to its final version, with the selected db and all — sinaza
– sinaza, Commented Jan 11, 2016 at 10:48
How do people expect to get correct responses when the code they post is not complete? — Professor Abronsius
– Professor Abronsius, Commented Jan 11, 2016 at 10:50
Tip (for both OP and commenters): if you have an error in a given line of code, the error cannot be caused by the lines of code that execute afterwards. — Álvaro González
– Álvaro González, Commented Jan 11, 2016 at 11:02

Clay · Accepted Answer · 2016-01-11 10:55:46Z

1

You need to specify a DSN when instantiating, replace testdb with the name of your database.

Change localhost to something like this mysql:dbname=testdb;host=127.0.0.1.

$db = new PDO ("mysql:dbname=testdb;host=localhost", "root", "");
$query = $db->prepare("SELECT * FROM comments");
$query->execute();
while($fetch = $query->fetch(PDO::FETCH_ASSOC)){
    $name = $fetch['name'];
    $message = $fetch['comment'];
    echo "<li class='com'><b>".ucwords($name)."</b> - ".$message."</li>";
}

Read more here: http://php.net/manual/en/pdo.construct.php

Usage: public PDO::__construct ( string $dsn [, string $username [, string $password [, array $options ]]] )

edited Jan 11, 2016 at 10:55

answered Jan 11, 2016 at 10:48

Clay

4,7683 gold badges37 silver badges49 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Clay Over a year ago

Be sure to use the checkbox to accept the answer since it resolves your question, thank you

Rpi programmer Over a year ago

It tells me that I can't give +1 because I haven't got 15 reputation.

Clay Over a year ago

You can click the checkbox and out will accept the answer. The checkbox is below the down vote arrow,

Collectives™ on Stack Overflow

PHP $db PDO connection error

1 Answer 1

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related