更改我的输出格式

Question

my php code is :

$q = $db->query("SELECT username FROM users LIMIT 3");
$users = array();
while($row = $db->fetchAll($q))
{
    $users[] = $row;
}


foreach($users as $user)
{


echo $user['username'].'<br>';

}

and the output will be

Nilsen
Michael
Sam

Does it possible to change my output format to be Nilsen,Michael,Sam without start foreach ?

Any idea please ?

Thank you.

Answer 1

while($row = $db->fetchAll($q)) // fetchAll is wired here, but since you get the result, asume that's right
{
    $users[] = $row['username'];
}

then use:

echo join(',' $users);

Answer 2

you can use GROUP_CONCAT() and loop won't be needed on the php side.

SELECT GROUP_CONCAT(username) user_name FROM users LIMIT 3

• MySQL GROUP_CONCAT()

Answer 3

$q = $db->query("SELECT username FROM users LIMIT 3");
while($row = $db->fetchAll($q))
{
   print_r($row);
}

.

or

 echo $row[0], $row[1], $row[2]; 

I wouldn't recommend this for production though, just for checking/debuging..

Answer 4

Mostly for debugging you can use like this :

$q = $db->query("SELECT username FROM users LIMIT 3");
while($row = $db->fetchAll($q))
{
    print_r($row); // or below
    var_dump($row);
}

The var_dump() function displays structured information about variables/expressions including its type and value. Arrays are explored recursively with values indented to show structure. It also shows which array values and object properties are references.

The print_r() displays information about a variable in a way that's readable by humans. array values will be presented in a format that shows keys and elements. Similar notation is used for objects.

Answer 5

Do you mean this?

$stmt = $db->query('SELECT username FROM users LIMIT 3');

$rows = $stmt->fetchAll(PDO::FETCH_ASSOC);

$users = array_map(function($row) {
    return $row['username'];
}, $rows);

print_r($users);