mysqli_query not working when called from inside a function

Question

Here is my code:

<?php
$db_host        = 'localhost';
$db_user        = 'root';
$db_pass        = 'root';
$db_database    = 'drmahima_com';
$link = mysqli_connect($db_host,$db_user,$db_pass,$db_database) or die('Unable to establish a DB connection');
mysqli_query($link, "SET names UTF8");
function temp() {
    $patient = mysqli_fetch_assoc(mysqli_query($link, "SELECT name,dob FROM patients WHERE id='69'"));
    echo $patient['name'];
}
temp();
?>

When I run this, the query doesn't seem to execute and nothing shows up on the page. However, if I remove the function and just change the code to this:

<?php
$db_host        = 'localhost';
$db_user        = 'root';
$db_pass        = 'root';
$db_database    = 'drmahima_com';
$link = mysqli_connect($db_host,$db_user,$db_pass,$db_database) or die('Unable to establish a DB connection');
mysqli_query($link, "SET names UTF8");
// function temp() {
    $patient = mysqli_fetch_assoc(mysqli_query($link, "SELECT name,dob FROM patients WHERE id='69'"));
    echo $patient['name'];
// }
// temp();
?>

It works, and the patient's name is displayed.

What is going on here?

its a scope issue. `$link` is out of scope, you'll need to pass the connection in the argument. `temp($link)` — Kevin, May 08 '15 at 09:57
Because of Scope. http://php.net/manual/en/language.variables.scope.php . If you still wanna use outside variable in function, you can declare `global $link;` inside function and you'll be good. — Bhavesh G, May 08 '15 at 10:17

score 0 · Answer 1 · edited May 08 '15 at 10:04

0

Pass $link to the function. It is not working because of the scope of that variable. Try with -

function temp($link) {
    $patient = mysqli_fetch_assoc(mysqli_query($link, "SELECT name,dob FROM patients WHERE id='69'"));
    echo $patient['name'];
}
temp($link);

edited May 08 '15 at 10:04

Kevin

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answered May 08 '15 at 10:03

Sougata Bose

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score 0 · Answer 2 · answered May 08 '15 at 10:03

Pass the $link to function as a parameter. Try this:

<?php
$db_host        = 'localhost';
$db_user        = 'root';
$db_pass        = 'root';
$db_database    = 'drmahima_com';
$link = mysqli_connect($db_host,$db_user,$db_pass,$db_database) or die('Unable to establish a DB connection');
mysqli_query($link, "SET names UTF8");
function temp($link) {
    $patient = mysqli_fetch_assoc(mysqli_query($link, "SELECT name,dob FROM patients WHERE id='69'"));
    echo $patient['name'];
}
temp($link);
?>

mysqli_query not working when called from inside a function

2 Answers2