Select Number of Values in Database Column - php

Question

I have a mySQL table called palettes, and I want to return the number of links in the table. Basically, I want to return the number of values in the link column. (In this case, 6).
I tried using this code, but it didn't work. I'm a front-end dev, with NO knowledge of php or anything..
include "mysql.php";
$select_rows = $mysqli->query("SELECT COUNT(link) FROM palettes");
$rows = mysqli_fetch_array($select_rows);
$total = $rows[0];
echo $total;
The above code should or echoed 6, right? Selecting from column link
This is what my table looks like:

Answer 1

Use the WHERE clause with LIKE 'http%' and change your query to count id's that fit:
First, I'll assume your file 'mysql.php' has a connection to the database somewhere in the file like this:
<?php
if (session_status() !== PHP_SESSION_ACTIVE) {session_start();}
$hostname = 'localhost';
$dbname = 'myDatabaseName';
$username = 'admin';
$password = 'myPassword';
$cxn = mysqli_connect($hostname, $username, $password, $dbname) or DIE('Connection to host is failed, perhaps the service is down!');
?>//End connect.php
Now you can try this:
include 'mysql.php';
$select_rows = mysqli_num_rows(mysqli_query($cxn, "SELECT id FROM palettes WHERE link LIKE 'http%'"));
echo $select_rows; //Should = 6

Answer 2

I would say place NULL in case you don't have the link available:
You can do it by making the Link column to allow NULL as default. You can make use of the COUNT(Link) in that case. This is recommended.
If you have to have empty string instead of NULLs.
select sum(if(Link != "",1,0)) counting from palettes;
Or if you can make sure all the links start with http/https
select sum(if(Link like "http%",1,0)) counting from palettes;