PHP error help needed

[jackcoder]

hello I keep getting these errors:

 

Warning: mysql_query() expects parameter 2 to be resource, string given in C:\xampp\htdocs\PHP & JQUERY\WEBSITE\index.php on line 17

Warning: mysql_fetch_assoc() expects parameter 1 to be resource, null given in C:\xampp\htdocs\PHP & JQUERY\WEBSITE\index.php on line 19

 

This is the code I am using:

 

$conn = mysql_connect("localhost", "root");

$q = "SELECT * FROM users";

$r = mysql_query($conn, $q);

 

$retrieve = mysql_fetch_assoc($r);

 

print $retrieve['user_name'];

 

Any help would be appreciated.

 

 

[jackcoder]

changed code to:

 

$conn = mysql_connect("localhost", "root", "", "users");

 

$data = mysql_query("SELECT * FROM users") or die(mysql_error());

$info = mysql_fetch_assoc($data);

 

echo $info['user_name'];

[CroNiX]

You really shouldn't use the mysql driver. It's been deprecated and your code won't work on newer php versions so it's kind of obsolete from the get-go. You won't do yourself any favors learning something that is obsolete.

http://php.net/manual/en/migration55.deprecated.php

You really should learn to use PDO, and if not that, use the mysqli (with an i) driver.

Edited August 3, 2014 by CroNiX

[jackcoder]

thank you!

[cyberRobot]

Out of curiosity, were you able to get the query working? It looks like you corrected the argument order for mysql_query()...so it's probably fixed.

[mogosselin]

This is an example with mysqli_ + OOP style:

<?php
define('DB_SERVER', "localhost");
define('DB_USER', "user");
define('DB_PASSWORD', "password");
define('DB_TABLE', "db_name");

$conn = new mysqli(DB_SERVER, DB_USER, DB_PASSWORD, DB_TABLE);

if ($conn->connect_error) {
  trigger_error('Database connection failed: '  . $conn->connect_error, E_USER_ERROR);
}

$query = "SELECT * FROM users";
$result = $conn->query($query);
 
if($result === false) {
  trigger_error('Wrong SQL: ' . $query . ' Error: ' . $conn->error, E_USER_ERROR);
} else {
    $result->data_seek(0);
    while($row = $result->fetch_assoc()){
        echo $row['username'] . '<br>';
    }  
}

$result->free();
$conn->close();

?>

Here's an example with mysqli_, procedural style:

<?php

define('DB_SERVER', "localhost");
define('DB_USER', "user");
define('DB_PASSWORD', "password");
define('DB_TABLE', "db_name");

// The procedural way
$mysqli = mysqli_connect(DB_SERVER, DB_USER, DB_PASSWORD, DB_TABLE);

if (mysqli_connect_errno($mysqli)) {
    trigger_error('Database connection failed: '  . mysqli_connect_error(), E_USER_ERROR);
}

$query = "SELECT text AS txt FROM `table_test`";
$result = mysqli_query($mysqli, $query) or trigger_error("Query Failed! SQL: $query - Error: ". mysqli_error($mysqli), E_USER_ERROR);

if($result) {
    while($row = mysqli_fetch_assoc($result)) {
        echo $row['txt'] . '<br>';  
    }
} 

mysqli_close($mysqli);

?>

This is an example with PDO:

$db = new PDO("server", "username", "password");
$statement = $db->prepare("select * from users");
$statement->execute();
$row = $statement->fetch();

• Please consider specifying the names of the fields instead of SELECT *. This is a, generally, a bad practice to use * (security & performance wise).
• As it's already been said, don't use mysql_ but mysqli_ or PDO.