php for loop is not returning all values, why?

Question

I started learning PHP and Databases today.

What I tried so far and worked is to access information from a database using a simple updateScores.php file.

DB high_scores:

  names  | scores |
___________________
 player1 |  20    |

 player2 |  69    |

My code:

$host="localhost";
$database="players";
$user="root";
$password = "";
$error = "Cant connect";

$con = mysqli_connect($host, $user, $password);
mysqli_select_db($con, $database) or die("Unable to connect!");

$query = "SELECT * FROM high_scores";
$result = mysqli_query($con, $query);
$n = mysqli_num_rows($result);

for($i=0; $i<$n; $i++){

    $name = mysqli_fetch_assoc($result)["name"];
    $score = mysqli_fetch_assoc($result)["score"];
    echo "Name  : ".$name;
    echo "Score : ".$score;
}
?>

This works fine when i execute http://localhost/updateScores.php

However when i change the last two lines to

echo $name."\t";
echo $score."\n";

I only get the first name (player1) and the last score (69) Why this is happening? Any help and additional link would be great. Thanks.

use: header('Content-Type: text/plain'); for it to work in browser — jibsteroos
– jibsteroos, Commented Sep 4, 2019 at 22:17

Nick · Accepted Answer · 2019-09-04 22:17:47Z

4

Your problem is that your for loop has two calls to mysqli_fetch_assoc, each of which fetches a new row from the database:

$name = mysqli_fetch_assoc($result)["name"];
$score = mysqli_fetch_assoc($result)["score"];

So you will end up getting the name from one row with the score from the next. The normal way of writing this loop is using while, with the fetch as the condition for the loop and then accessing the individual values from the fetched row:

while ($row = mysqli_fetch_assoc($result)) {
    $name = $row["name"];
    $score = $row["score"];
    echo "Name  : ".$name;
    echo "Score : ".$score;
}

answered Sep 4, 2019 at 22:17

Nick

147k23 gold badges67 silver badges106 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Dharman · Accepted Answer · 2019-09-04 22:27:48Z

2

MySQLi result is traversable. You could simply use foreach.

$result = mysqli_query($con, $query);
foreach($result as $row) {
    echo "Name  : ".$row['name'];
    echo "Score : ".$row['score'];
}

answered Sep 4, 2019 at 22:27

Dharman♦

33.9k27 gold badges106 silver badges157 bronze badges

Collectives™ on Stack Overflow

php for loop is not returning all values, why?

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related