PDO - Call to a member function fetch() on a non-object [duplicate]

Answer 1

Instead of:

$query = $db->query("SELECT articles . title FROM articles");

Try:

$query = $db->query("SELECT title FROM articles");

edit

Try:

while ($row = $query->fetch(PDO::FETCH_ASSOC)) {
    echo $row['title'];
}

Answer 2

PDO::query() returns false (which obviously is a non-object) if the query fails. So that's your problem. Your query has an error.

I recommend you to set the error mode in PDO.

$db->setAttribute(PDO::ATTR_ERRMODE, PDO:ERRMODE_EXCEPTION);

and then catch the error to see what is wrong with your query.

The different error modes that exist is PDO::ERRMODE_SILENT, PDO::ERRMODE_WARNING and PDO:ERRMODE_EXCEPTION. You can read about them in the PHP manual on PDO. Knowing how to debug when writing SQL is important and the key to not having to ask these kind of questions.

About your other problem

You gotta select the id column if you want to use it.

SELECT * FROM articles

or

SELECT id, title FROM articles

Answer 3

This error almost always means that your query didn't work the way you wanted it to, and as a result $query is null (or false?) and not a query result object. Try echoing db->errorinfo() and see if it tells you what went wrong.

You can also try pasting the text of your query into mysql directly and seeing what the result is. If that appears to work correctly, then the problem might be with your database connection code.