MySQL PDO无法从表中进行选择

Question

I am trying to learn mySQL PDO .. read tutorial after tutorial and trying to apply different ways to perform a simple SELECT statement.

Here is my latest attempt:

<?
include("inc/connPDO.php"); // hostname, username and password and dbName are in here
try {
$dbh = new PDO("mysql:host=$hostname;dbname=$dbName", $username, $password);
/*** echo a message saying we have connected ***/
echo 'Connected to database';   // this outputs appropriately

/*** The SQL SELECT statement ***/
$sql = "SELECT * FROM rofWeapons";
echo '<p>'.$sql;
foreach ($dbh->query($sql) as $row){   // *** line 11 error 
    print $row['weaponName'] .' - '. $row['weaponType'] . '<br />';
}


/*** close the database connection ***/
$dbh = null;    
}
    catch(PDOException $e)
{
    echo $e->getMessage();
}

?>

The output is the following:

Connected to database

SELECT * FROM rofWeapons

Warning: Invalid argument supplied for foreach() in /home/path/to/script/script.php on line 11

I am following a tutorial.. the foreach looks good. Why is it an invalid argument?

When I enter "SELECT * FROM rofWeapons" into mySQL queries the table perfectly fine.

A little help please?

Another Attempt

If I try a PREPARE statement:

/*** The SQL SELECT statement ***/
$weaponType=1;
    $sql = "SELECT * FROM rofWeapons WHERE weaponType=:weaponType";

$stmt = $dbh->prepare($sql);   // *** error Line 12 ***
$stmt->bindValue(':weaponType', $weaponType, PDO::PARAM_INT);
$stmt->execute();
$stmt->setFetchMode(PDO::FETCH_ASSOC); 

while($row = $stmt->fetch()) {
        print $row['weaponName'] .' - '. $row['weaponType'] . '<br />';
    }

I get no error. Nothing at all.

This is very frustrating. What am I doing wrong?

Answer 1

You have not fetched the array for using in the loop.

Change:

foreach ($dbh->query($sql) as $row){
    //YOUR CODE STUFF
}

To:

foreach ($dbh->query($sql)->fetchAll as $row){
    //YOUR CODE STUFF
}

It works fine.

Answer 2

Im not sure if this would fix your problem but you may want to try this:

$sql = "SELECT * FROM rofWeapons";
$sth = $dbh->query($sql);
while($row = $sth->fetch(PDO::FETCH_ASSOC))
{
     print $row['weaponName'] .' - '. $row['weaponType'] . '<br />';
}