How to test PHP 7 and WordPress MySQL/MariaDB Database connectivity using a PHP script

To test PHP 7 and WordPress MySQL/MariaDB database connectivity using a PHP script, you can use the mysqli_connect function to establish a connection to the database and the mysqli_query function to execute a SQL query.

Here is an example of a PHP script that tests MySQL/MariaDB database connectivity:

<?php
// Connect to MySQL/MariaDB database
$link = mysqli_connect('hostname', 'username', 'password', 'database');

// Check connection
if (!$link) {
    die('Error: Could not connect to database');
}

// Execute SQL query
$result = mysqli_query($link, 'SELECT * FROM table');

// Check query result
if (!$result) {
    die('Error: Could not execute SQL query');
}

// Print query result
while ($row = mysqli_fetch_assoc($result)) {
    print_r($row);
}

// Close connection
mysqli_close($link);
?>

This script establishes a connection to the MySQL/MariaDB database using the mysqli_connect function and then executes a SQL query using the mysqli_query function. If the connection is successful and the query executes successfully, the script will print the query result. If the connection or query fails, the script will print an error message.

By using the mysqli_connect and mysqli_query functions, you can test PHP 7 and WordPress MySQL/MariaDB database connectivity using a PHP script. It's always a good idea to carefully review the documentation and use the appropriate functions and syntax when working with MySQL/MariaDB databases in PHP. This will help ensure that your code is correct and that any problems are detected and addressed.