displaying results from mysql with php foreach.... very confused - php

Question

Hi I'm getting confused as to how to display results with foreach loops. It seems there are slight differences depending on the structure of the array? ie if its a simple array, associative or multi-dimensional? I have looked at other answers for this site but I am still very much confused.
i have connected to mysql db with this code
try
{
$pdo = new PDO('mysql:host=localhost;dbname=****', '*****',
'*****');
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$pdo->exec('SET NAMES "utf8"');
}
catch (PDOException $e)
{
$error = 'Unable to connect to the database server.' . $e->getMessage;
echo $error;
exit();
}
//next i want to retrieve the 'id' and 'name' from a db table...
$results = $pdo->query('select id, name FROM author');
//now I want to display those results on the page... i tried a foreach loop...
foreach ($results as $result) {
echo $result;
}
//but this just displays error message...
Parse error: syntax error, unexpected '$results' (T_VARIABLE), expecting '(' in C:\xampp\htdocs\Connect\admin\authors\test.php on line 6
Please help as im very confused. I just want to know how to display results from a db query like this with a foreach, and what rules apply when displaying different kinds of results from such queries.
I think it involves writing a foreach something like this ....
foreach ($results as $result=> $item) {
echo $item;
}
but i dont undertsand this either.
Any simplified approach to this would be greatly appreciated as I have been stuck on this for some time.
Thanks Rob.

Answer 1

$result is an array not the string.
$stmt = $pdo->prepare("SELECT id, name FROM author");
$stmt->execute();
$results = $stmt->fetchAll();
foreach ($results as $result) {
echo $result['id'];
echo $result['name'];
}
or print the array like this,
foreach ($results as $result) {
print_r($result);
}

Answer 2

You could try it with prepared statements, I always do even if I am not injecting parameters, keeps things a bit clearer.
$stmt = $pdo->prepare('select id, name FROM author');
$stmt->execute();
while($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
print_r($row);
}
You can use the statement fetch method, and with the constant PDO::FETCH_ASSOC to ensure each row is an associative array.

Answer 3

If you're just looking to SELECT something from a database, below is the general format of what you'll need:
try {
//First, you initialise a connection to the database (in this case I'm using *constants*).
$dbh = new PDO('mysql:host=localhost; dbname='.DB_NAME, DB_USER, DB_PASS);
//Secondly, we'll prepare our query - SELECT the id and name FROM table author
$stmt = $dbh->prepare("SELECT id, name FROM author");
// Then we must execute the query
$stmt->execute();
// After execution, we must perform some function to get the results
// This function fetches ALL the results as an array so we can loop
// through them with foreach.
// (Other methods include a while loop and "fetch()" for one row at a time)
$results = $stmt->fetchAll();
// Then we just loop through everything
foreach ($results as $row) {
echo $row['id'];
echo $row['name'];
}
} catch (PDOException $e) {
echo $e->getMessage();
}