php script not sending query to mysql db?

Question

The below code I got from the w3 schools website and adapted it a little to my db but no matter what when I click on my search button I only get the first line printed and nothing else. It doesn't even print if the connection to my db is successfully made or not.

I used chrome's dev tool to check my network traffic and I can see my POST request made successfully:

name: bahamas submit: Search

I enabled logging for both error and general on my mysql instance, and did a grep for bahamas and got no hits. So this would seem to indicate that the script didn't even query my db?

IE this is what I get: https://imgur.com/a/PHKBmbU

   <?php echo("PHP Search Page Loaded Successfully"); 


   if(isset($_POST['submit'])){


        if(preg_match("^/[A-Za-z]+/", $_POST['name'])){
            $servername = "localhost";
            $username = "test";
            $password = "test";
            $dbname = "test";

            // Create connection
            $conn = new mysqli($servername, $username, $password, $dbname);
            // Check connection
            if ($conn->connect_error) {
                die("Connection failed: " . $conn->connect_error);
            } else {
                echo("We are not dead");
            }

            $sql = "SELECT boatname, date, price FROM liveaboards";
            $result = $conn->query($sql);


            if ($result->num_rows > 0) {
                // output data of each row
                while($row = $result->fetch_assoc()) {
                    echo("<br> boatname: ". $row["boatname"]. " - date: ". $row["date"]. " " . $row["price"] . "<br>");
                }
            } else {
                echo(" 0 results");
            }

            $conn->close();

        }
    }else{
        echo("<p>Please enter a search query</p>");
    }

?>

Answer 1

In following the theme of W3 Schools (one of my favorite resources), here is the correct way to sanitize data: https://www.w3schools.com/php/php_filter.asp

Applied to your code:

   <?php echo("PHP Search Page Loaded Successfully"); 
// test variables.    
$_POST['submit'] = true;
$_POST['name'] = "bahamas";

   if(isset($_POST['submit'])){
            $_POST['name'] = filter_var($_POST['name'], FILTER_SANITIZE_STRING);
            $servername = "localhost";
            $username = "test";
            $password = "test";
            $dbname = "test";

            // Create connection
            $conn = new mysqli($servername, $username, $password, $dbname);
            // Check connection
            if ($conn->connect_error) {
                die("Connection failed: " . $conn->connect_error);
            } else {
                echo("We are not dead");
            }

            $sql = "SELECT boatname, date, price FROM liveaboards";
            $result = $conn->query($sql);


            if ($result->num_rows > 0) {
                // output data of each row
                while($row = $result->fetch_assoc()) {
                    echo("<br> boatname: ". $row["boatname"]. " - date: ". $row["date"]. " " . $row["price"] . "<br>");
                }
            } else {
                echo(" 0 results");
            }

            $conn->close();


    }else{
        echo("<p>Please enter a search query</p>");
    }

?>

Answer 2

According to your POST result, you are receiving name: bahamas submit: Search , if so then Correct this

if(isset($_POST['submit'])){

TO 

if(isset($_POST['Search'])){