108
votes

I am doing a tutorial and am getting this error:

Fatal error: Class 'MySQLi' not found (LONG URL) on line 8

The code on line 8 is:

$mysqli = new MySQLi($db_server, $db_user, $db_pass, $db_name);

I saw online someone said to see if it was turned on in my phpinfo(), but there wasn't anything listed in there under for "mysqli".

Also, I am running PHP version 5.2.5

25
You can use a handwritten MYSQLi class, so you don't need to install mysqli. It's the only solution if you don't own the server.chickens
On PHP 7.4 at least the class name is lowercase new mysqli()undefined

25 Answers

94
votes

Sounds like you just need to install MySQLi.

If you think you've done that and still have a problem, please post your operating system and anything else that might help diagnose it further.

48
votes

You can check if the mysqli libraries are present by executing this code:

if (!function_exists('mysqli_init') && !extension_loaded('mysqli')) {
    echo 'We don\'t have mysqli!!!';
} else {
    echo 'Phew we have it!';
}
39
votes

If you are on Ubuntu, run:

 sudo apt-get install php-mysqlnd
26
votes

If you're calling "new mysqli(..)" from within a class that is namespaced, you might see a similar error Fatal error: Class 'foo\bar\mysqli' not found in. The way to fix this is to explicitly set it to the root namespace with a preceding backslash like so:

<?php 
$mysqli = new \MySQLi($db_server, $db_user, $db_pass, $db_name);
15
votes

In addition to uncommenting the php_mysqli.dll extension in php.ini, also uncomment the extension_dir directive in php.ini and specify your location:

extension_dir = "C:\software\php\dist\ext"

This made it work for me.

5
votes

My OS is Ubuntu. I solved this problem by using:

sudo apt-get install php5-mysql
3
votes

If you are on Docker...

Inside php-container RUN:

#docker-php-ext-install mysqli

#apachectl restart
2
votes

Seems like problem with your installation.

  • Have you installed MySQLi?
  • Have you activated it in php.ini?
  • Restarted Apache and/or PHP-FPM?

http://www.php.net/manual/en/mysqli.installation.php

2
votes

How to Enable mysqli in php.ini

  1. Edit/uncomment by removing ';'(colon) the following config in php.ini: 1st (uncomment and add config):
    include_path = "C:\php\includes"
    
    2nd (uncomment):
    extension_dir = "ext"
    
    3rd (uncomment and edit config):
    extension=C:/PHP/ext/php_mysql.dll
    extension=C:/PHP/ext/php_mysqli.dll
    
  2. Restart the IIS server
  3. Make sure that mysql is running on the system.

How to load php.ini file

  1. Rename any one of the file php.ini-production/php.ini-development to php.ini from C:\PHP(note now the extention will be ini i.e "php.ini").
  2. After renaming to php.ini file restart server
  3. See the changes in http://localhost/phpinfo.php
1
votes

On a fresh install of PHP, remove ; before extension_dir in php.ini.

1
votes

For anyone using docker, I ran into this issue, and resolved it by using my own Dockerfile instead of the php:fpm image:

FROM php:fpm

RUN docker-php-ext-install mysqli
1
votes

I thought I might help anybody with the same problem using Namesco servers. I have been trying to fix this problem after moving a database from my local server on home pc to namesco. They would not assist they said it was a coding issue.

  • However, it was simple to fix from their CPANEl LINUX hosting interface.
  • Click on php.
  • then click on php modules and from their list of preinstalled modules just click the box for mysqli.
  • Then click save. (No need to change code if it worked(s) on another server.)

Unfortunately, their support articles were a waste of time. After reading this I went to admin interface with a new determination.

0
votes

Some distributions (such as Gentoo) support multiple installations of PHP, and you have to make sure you're using one with mysqli installed and enabled.

On Gentoo, I had installed a new PHP (with the mysqli USE flag enabled), but I needed to activate the new version of PHP (since the old one must have been missing mysqli):

# eselect php list apache2
  [1]   php5.3 *
  [2]   php5.5
# eselect php set apache2 2
You have to run `/etc/init.d/apache2 restart' for the changes to take effect
# /etc/init.d/apache2 restart
0
votes

I checked all above and it didn't work for me,

There are some steps I found.

I used PHP Version 5.5.9-1ubuntu4.17 on Ubuntu 14.04

First check the folder

#ls /etc/php5/mods-available/
json.ini  mcrypt.ini  mysqli.ini  mysql.ini  mysqlnd.ini  opcache.ini  pdo.ini  pdo_mysql.ini  readline.ini  xcache.ini

If it did not contain mysqli.ini, read other answer for installing it,

Open php.ini find extension_dir

In my case , I must set extension_dir = /usr/lib/php5/20121212

And restart apache2 : /ect/init.d/apache2 restart

0
votes

The PHP zip includes most of the commonly used extensions (*.dll on windows such as php_mysqli.dll) under the \ext directory, however they are not enabled by default. You might be getting this Fatal Error when trying to use MySQLi:

( ! ) Fatal error: Uncaught Error: Class 'mysqli' not found in C:\myProject\ class.Database.php on line 24

To enable extensions, open php.ini (you might need to first copy php.ini-development as php.ini), and un-comment (or add) these two lines:

extension_dir = "ext"

And any particular extensions you are getting Fatal Errors for, i.e. for mysqli:

extension=mysqli
0
votes

on ubuntu:

sudo apt-get install php-mysql
sudo service apache2 restart
0
votes

on Debian 10

apt install php-mysql

/etc/init.d/apache2 restart
0
votes

I found a solution for this problem after a long analysing procedure. After properly testing my php installation with the command line features I found out that the php is working well and could work with the mysql database. Btw. you can run code-files with php code with the command php -f filename.php
So I realized, it must something be wrong with the Apache.
I made a file with just the phpinfo() function inside.
Here I saw, that in the line
Loaded Configuration File
my config file was not loaded, instead there was mentioned (none).

Finally I found within the Apache configuration the entry

<IfModule php5_module>
    PHPINIDir "C:/xampp/php"
</IfModule>

But I've installed the PHP 7 and so the Apache could not load the php.ini file because there was no entry for that. I added

<IfModule php7_module>
    PHPINIDir "C:/xampp/php"
</IfModule>

and after restart Apache all works well.

These code blocks above I found in my httpd-xampp.conf file. May it is somewhere else at your configuration.
In the same file I had changed before the settings for the php 7 as replacement for the php 5 version.

#
# PHP-Module setup
#
#LoadFile "C:/xampp/php/php5ts.dll"
#LoadModule php5_module "C:/xampp/php/php5apache2_4.dll"
LoadFile "C:/xampp/php/php7ts.dll"
LoadModule php7_module "C:/xampp/php/php7apache2_4.dll"

As you can see I have the xampp package installed but this problem was just on the Apache side.

0
votes

install phpXX-extension by PHP. In my FreeBSD's case:

pkg install php74-extensions
0
votes

I'm using xampp and my problem was fixed once i rename:

extension_dir = "ext"

to

extension_dir = "C:\xampp\php\ext"

PS: Don't forget to restart apache after making this change!

0
votes

In php.ini :

extension_dir ="c:/wamp64/bin/php/php7.4.9/ext/"

Make sure the PHP version is correct.

0
votes
  1. Open your PHP folder.
  2. Find php.ini-development and open it.
  3. Find ;extension=mysqli
  4. delete the ; symbol
  5. save file and change the file extension from php.ini-development to php.ini
  6. Restart the server and test the code:
    if (!function_exists('mysqli_init') && !extension_loaded('mysqli')) {  
            echo 'We don\'t have mysqli!!!';  
     } else {  
         echo 'mysqli is installed';
     }
  1. if it not working, change both extension_dir in php.ini from "ext" to "c:\php\ext" and extension=mysqli to extension=php_mysqli.dll then test again Remember to reset the server every time you test
0
votes

All you have to do is go to the php.ini file and on line 926 (depending on version) delete #. It should look like this:

;extension=ldap
;extension=mbstring
;extension=exif
extension=mysqli
;extension=oci8_12c
;extension=odbc

Save the file and open console (cmd) as administrator. Go to the path Apache24 / bin and enter httpd -k restart. This command will restart your server. After that, refresh the page and everything should work.

0
votes

When I tried my PHP web app it was giving me the same error.

By googling I found out the MySQL plugin for the PHP server was missing with my installation. I am using Ubuntu, so when I tried MySQL plugin for PHP I found out 2 are there,

php-mysql and php<version>-mysql

I issued command - php --version in my terminal, I was having php7.4,

again I issued apt install php7.4-mysql

It worked.

-2
votes
<?php  /* If the error is due to calling mysqli in a class */

    class dbconnect extends mysqli{

        private $host = 'localhost';
        private $user = 'root';
        private $pass = '';
        private $db = 'test';

        public function __construct() {
            parent::__construct($this->host, $this->user, $this->pass, $this->db);

            if (mysqli_connect_error()) {
                die('Connect Error (' . mysqli_connect_errno() . ') ' .
                    mysqli_connect_error());
            }
        }
    }
?>