mysqli does not work
Uncaught Error: Call to undefined function mysqli_connect() in /workspace/php_study/index.php:If
mysqli does not working with the above error message,
Install the package (php7.3-mysql) for mysqli and run again.Please enter the command below to install:
sudo add-apt-repository ppa:ondrej/php
sudo apt-get update
sudo apt-get install php7.3-mysql