Fetching data from mysql database with php

Question

I just created a page that could get the name of the students in 2 schools using their school name(This is just for my practice). But when i execute the following code i don't get the name of the top student in each school whose name is at top in the database, But i get the rest of the list.

<?php
require 'connect.php';

if(isset($_GET['school']))
{
    $school = trim($_GET['school']);
    $people = $db->prepare("SELECT id, name FROM users WHERE school = ? ");
    $people->bind_param('s', $school);
    $people->execute();
    $people->bind_result($id, $name);

    if(!$people->fetch())
    {
        echo "Invalid School Name!!";       
    }   
    else
    {
        while($people->fetch())
        {
            echo 'ID. ',$id, ' ',$name,'<br>';
        }
    }
}
?>

This problem only occurs when i use if and else statements to output error message "Invalid School Name!!". If i just use the while loop to fetch data, i get the full list. Please tell me the why i miss the first name and a solution for this. Thank you.

@Prix No, if (!$people->fetch()) is correct (partially)

Michael Berkowski
– Michael Berkowski

2014-09-14 23:45:03 +00:00
Commented Sep 14, 2014 at 23:45 — Michael Berkowski
– Michael Berkowski, Commented Sep 14, 2014 at 23:45
Can you choose an answer if you're problem is solved? Thx

ochurlaud
– ochurlaud

2014-09-18 10:02:57 +00:00
Commented Sep 18, 2014 at 10:02 — ochurlaud
– ochurlaud, Commented Sep 18, 2014 at 10:02

ochurlaud · Accepted Answer · 2014-09-14 23:48:04Z

2

Your first test does $people->fetch(). If the answer is not false, then it does it again and execute the code in the loop until the last element. So your if is the problem because it pass the first element while doing the test.

To solve this, just remove your if-condition: if the query doesn't find any people,

while( $people->fetch() ) {
 Do_something(); }

...will be jumped and everything will work as expected.

To add the error message, use a try/catch or check whether you entered the loop or not with a boolean (maybe there are other methods, though).

answered Sep 14, 2014 at 23:48

ochurlaud

4106 silver badges14 bronze badges

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

1 Comment

Michael Berkowski Over a year ago

Not a try/catch, because it wouldn't throw an exception (it would return false). Instead, just call fetchAll() once and test the count() of the resultant array. If it's zero, show the error, if it's nonzero, do a foreach over the array to output data.

RobbieP · Accepted Answer · 2014-09-15 00:00:37Z

0

Change the conditional to test against the result

$people->execute();
$people->store_result();
$people->bind_result($id, $name);

if($people->num_rows == 0)
{
    echo "Invalid School Name!!";       
}   
else
{
    while($people->fetch())
    {
        echo 'ID. ',$id, ' ',$name,'<br>';
    }
}

answered Sep 15, 2014 at 0:00

RobbieP

6984 silver badges13 bronze badges

Collectives™ on Stack Overflow

Fetching data from mysql database with php

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related