Can't access fetched data from PDO query [closed] - php

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I am trying to create a dropdown-list with options (genres) from my database. For example if I have comedy, thriller and action in my database, these genres will be available as options on my dropdown-list. Basically what happens is that I get a blank list with no options and I was wondering if there is any problem with my code. Thanks in advance.
<?php
$sql = 'SELECT DISTINCT Genre.name FROM (Genre JOIN Movie2Genre ON Genre.id = Movie2Genre.idGenre)';
$stmt = $db3->prepare($sql);
$stmt->execute();
$allGenre = $stmt->fetchAll();
echo "<select>";
foreach ($allGenre as $val){
echo "<option value='{$val["name"]}'>{$val["name"]}</option>";
}
echo "</select>";
?>

Answer 1

As it turned out in the comments you set your default fetch mode with setAttribute(). So you fetch your data as an object and not as an array as it would be normal, with this:
$dbh->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_OBJ);
Also a quote from the manual where it says which mode is default:
PDO::FETCH_BOTH (default): returns an array indexed by both column name and 0-indexed column number as returned in your result set
So instead of this structure:
Array
(
[0] => Array
(
[id] => 1
[0] => 1
[number] => 3234
[1] => 3234
[text] => sdfdsf
[2] => sdfdsf
[texttext] => sdfsdf
[3] => sdfsdf
)
//...
You have a structure like this:
Array
(
[0] => stdClass Object
(
[id] => 1
[number] => 3234
[text] => sdfdsf
[texttext] => sdfsdf
)
//...
So you need to use -> to access the object property like this:
$val->name
Side Notes:
Also if you would have added error reporting (only while staging, never in production!):
<?php
ini_set("display_errors", 1);
error_reporting(E_ALL);
?>
You would have received an error like this:
Fatal error: Cannot use object of type stdClass as array
And I would recommend you to enable error mode for your PDO connection (just put it right after the connection statement):
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
Then you can also put your db stuff in a try & catch block to catch PDOExceptions:
try {
//db stuff
} catch(PDOException) {
echo $e->getMessage();
}

Answer 2

Given your current code we can state that
you are not doing anything with $genre - you are outputting the <option> elements
there might not be any genres (i.e. $genre is not set)
If 1 is true, Consider putting the explode'd/joined value of $genre in an enclosing <select>docs tag.
In case of 2, the select will be empty. Because your question does not include the specific code for outputting the select, it's hard to say what is really the problem. Your question states "I can't select (drop)" so there might even be JavaScript changing the enabled-attribute of the (if any) outputted select.