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Emil Wallgren
11,737 PointsProblem with fetchAll() in PDO
Hi! I have this code:
<?php
public function showBlogForCategory() {
if (isset($_GET['category'])) {
$category = $_GET['category'];
$sql = 'SELECT * FROM blog WHERE category=? ORDER BY id DESC';
$prepared = $this->db->prepare($sql);
$executed = $prepared->execute(array($category));
$blogPosts = $executed->fetchAll(PDO::FETCH_ASSOC);
$newLine = '';
foreach ($blogPosts as $blogPost) {
$newLine .= '<h2><a href="nyhet.php?p='.$blogPost['id'].'">'.$blogPost['title'].'</a></h2>
<h4><i>Av: '.$blogPost['author'].'</i></h4>
<p>'.substr($blogPost['description'], 0, 200).'...</p>';
}
return $newLine;
}
}
But it's outputting this error message:
Fatal error: Call to a member function fetchAll() on a non-object in SECRET;-)
I cant find the problem...Do someone here understand what is wrong?
Regards!
/Emil
3 Answers
Ted Sumner
Courses Plus Student 17,967 PointsYou should always put your database work in try catch blocks. You also have connected to your database. Here is code I am using in a development context on my localhost. User name and passwords will be changed in live deployment.
<?php
try {
$db = new PDO("mysql:host=localhost;dbname=cubScout;charset=utf8mb4","root","");
$db->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);
} catch (Exception $e) {
echo $e->getMessage() . " dbCall Line 13";
exit;
}
Replace localhost with your database host's name. dbname is your database name. root is the user name and there is no password, hence the "".
The catch is nice. The $e->getMessage() returns the MySQL error and I add the file and line (approximate) so I can troubleshoot easily. I will probably make that more obtuse on deployment. Then you exit if there is an error.
This is where I query the database:
<?php
function full_scout_list() {
require('dbCall.php');
// require(ROOT_PATH . "inc/database.php");
try {
$results = $db->query("
SELECT FirstName, LastName, Den, Bobcat, Tiger, Wolf, Bear, Webelo, Arrow, Health, id
FROM scouts
ORDER BY Den DESC, LastName");
$scouts = array(array());
$scouts = $results->fetchAll(PDO::FETCH_ASSOC);
// $recent = array_reverse($recent);
return $scouts;
} catch (Exception $e) {
echo $e->getMessage() . "db.php full_scout_list Line 52";
exit;
}
}
This is code to fetch information from the database and do something similar to what you want to do:
<?php
require(ROOT_PATH . 'database_learn/db.php');
require(ROOT_PATH . 'database_learn/dbCall.php');
//step through array and display in table
// $scouts = array(array());
$scouts = full_scout_list();
//var_dump($scouts);
$t = '<th class="heading">Name</th><th class="heading">Den</th><th class="heading">Bobcat</th><th class="heading">Tiger</th><th>Wolf</th><th class="heading">Bear</th><th class="heading">Webelo</th><th class="heading">Arrow of Light</th>';
foreach ($scouts as $scout) {
$t = $t . '<tr>';
$t = $t . '<th class="row">' . $scout["FirstName"] . ' ' . $scout["LastName"] . '</th>';
$t = $t . '<td> ' . $scout["Den"] . '</td>';
$t = $t . '<td>' . $scout['Bobcat'] . '</td>';
$t = $t . '<td>' . $scout['Wolf'] . '</td>';
$t = $t . '<td>' . $scout['Bear'] . '</td>';
$t = $t . '<td>' . $scout['Webelo'] . '</td>';
$t = $t . '<td>' . $scout['Arrow'] . '</td>';
$t = $t . '</tr>';
}
The initial $t is not elegant and I want to figure out a way to do that better. I am trying to pull the column names and just have not had time to look it up. I think I can also clean up the code in the foreach loop with a count and while statement.
I did not get variables to work in my database queries. You can see some attempts in my commented out lines. I got frustrated and wanted to make it work before I went back to the variables. I ultimately want constants so I can put the code on GitHub without revealing the key information to let someone in.
miguelcastro2
Courses Plus Student 6,573 PointsNo need to be secretive about error dumps.
Are you sure you are connected to the database? You can wrap your execute statement around an if statement to see if it has executed properly:
<?php
$sql = 'SELECT * FROM blog WHERE category=? ORDER BY id DESC';
$prepared = $this->db->prepare($sql);
if ($executed = $prepared->execute(array($category)) ) {
echo "Statement executed successfully.";
} else {
$arr = $prepared->errorInfo();
print_r($arr);
}
Emil Wallgren
11,737 PointsCheck my answer below. Thanks for your support! :-)
/Emil
Emil Wallgren
11,737 PointsGot it working guys!!!
This is the proper code! Check what I changed in the variable $prepared!
<?php
public function showBlogForCategory() {
if (isset($_GET['category'])) {
$category = $_GET['category'];
$sql = 'SELECT * FROM blog WHERE category=? ORDER BY id DESC';
$prepared = $this->db->prepare($sql);
$prepared->execute(array($category));
$blogPosts = $prepared->fetchAll(PDO::FETCH_ASSOC);
$newLine = '';
foreach ($blogPosts as $blogPost) {
$newLine .= '<h2><a href="nyhet.php?p='.$blogPost['id'].'">'.$blogPost['title'].'</a></h2>
<h4><i>Av: '.$blogPost['author'].'</i></h4>
<p>'.substr($blogPost['description'], 0, 200).'...</p>';
}
return $newLine;
}
}
Emil Wallgren
11,737 PointsEmil Wallgren
11,737 PointsCheck my answer below. Thanks for your support! :-)
/Emil