Isn't this a duplicate of bug134982 ?
No problem here to connect to MariaDB with direct connection and the original packages from LO, versions LO 7.0.0.3 or LO 6.3.6.1 on OpenSUSE 15.1 64bit rpm Linux.

Maybe is the same problem, yes.
But there someone says to do a symlink from the lampp socket (in /opt) to "the place where LO expects to find it". 
But can you kindly tell me where is this place?
Thank you

(In reply to Duns from comment #2)
> Maybe is the same problem, yes.
> But there someone says to do a symlink from the lampp socket (in /opt) to
> "the place where LO expects to find it". 
> But can you kindly tell me where is this place?
> Thank you

It depends on your Linux distrib and therefore has nothing to do with LO, per se.

I would suggest looking up where Ubuntu 20.04 installs the Unix socket connection file when you install mysql server via the distrib provided package... 
at a guess, probably somewhere in /var/run/, cf. for example, here:


https://www.digitalocean.com/community/tutorials/how-to-install-mysql-on-ubuntu-20-04-fr

*** This bug has been marked as a duplicate of bug 134982 ***

I faced a similar issue when setting up MySQL on Ubuntu 20.04 and integrating it with PHP. The problem occurred due to MySQL's default `auth_socket` plugin for authentication, which often causes connection issues when using PHP. Here's how I resolved it, step-by-step:

---

### Step 1: Verify MySQL Installation  
Ensure that MySQL is installed and running on your Ubuntu system. You can confirm by checking the service status:  
```bash
sudo systemctl status mysql
```  
If MySQL isn’t installed, follow this comprehensive [tutorial on installing MySQL on Ubuntu 20.04](https://docs.vultr.com/how-to-install-mysql-on-ubuntu-24-04).

---

### Step 2: Identify the Unix Socket File  
Ubuntu places the MySQL socket file in `/var/run/mysqld/mysqld.sock` by default. You can confirm the location in the MySQL configuration file:  
```bash
sudo cat /etc/mysql/mysql.conf.d/mysqld.cnf
```  
Look for the line:  
```text
socket = /var/run/mysqld/mysqld.sock
```  

---

### Step 3: Adjust Root Authentication  
MySQL on Ubuntu 20.04 often uses the `auth_socket` plugin for the root user. This means you can connect without a password from the terminal but not from PHP. To fix this:  

1. Log into MySQL:  
   ```bash
   sudo mysql
   ```  

2. Change the authentication method for the root user:  
   ```sql
   ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'your_password_here';
   FLUSH PRIVILEGES;
   ```  

3. Test the new credentials by running:  
   ```bash
   mysql -u root -p
   ```  
   Enter the password you just set.

---

### Step 4: Test PHP Connection to MySQL  
Create a PHP file (`db_test.php`) to test the connection:  
```php
<?php
$servername = "localhost";
$username = "root";
$password = "your_password_here";
$dbname = "test_db";

// Create connection
$conn = mysqli_connect($servername, $username, $password, $dbname);

// Check connection
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}
echo "Connected successfully";
?>
```  

Place this file in your Apache web directory (usually `/var/www/html`) and open it in your browser. If everything is set up correctly, it should display:  
```text
Connected successfully
```  

---

### Step 5: Create a Dedicated MySQL User (Optional)  
For better security, create a dedicated user for your application:  
```sql
CREATE USER 'app_user'@'localhost' IDENTIFIED BY 'secure_password';
GRANT ALL PRIVILEGES ON test_db.* TO 'app_user'@'localhost';
FLUSH PRIVILEGES;
```  
Update your PHP script to use this new user's credentials.

---

### Additional Resources  
I found this tutorial on MySQL setup ) very helpful for understanding MySQL installation and configuration on Ubuntu. It also provides insights into handling authentication methods and optimizing your setup.

By following these steps, I was able to resolve the connection issue and properly integrate MySQL with PHP. Hopefully, this helps others facing the same challenge!