PHP Count Arrays from MySQL counts Incorrectly - php

Question

I am having trouble correctly counting elements within the array that I pulled from my database. Please see my code below:
// Create connection
$conn = mysqli_connect($servername, $username, $password, $dbname);
// Check connection
if (!$conn)
{
die("Connection failed: " . mysqli_connect_error());
}
echo "Connected successfully!";
//NEW QUERY TO OUR DATABASE
$query = $conn -> query("Select distinct Race from Races");
while($race[] = $query->fetch_object());
//Check how many elements are within our query
$racecount = count($race);
echo "<br>" . $racecount . "<br><br>";
$racecount = count($race,COUNT_RECURSIVE);
echo "<br>" . $racecount . "<br><br>";
var_dump($race);
echo "<br><br><br>";
Using both type count() in both ways yields the same result of "4". However, please see the result from my var_dump.
array(4) { [0]=> object(stdClass)#3 (1) { ["Race"]=> string(5) "Human" } [1]=> object(stdClass)#4 (1) { ["Race"]=> string(7) "Vampire" } [2]=> object(stdClass)#5 (1) { ["Race"]=> string(5) "Demon" } [3]=> NULL }
Var_dump shows that it is an array with 4 elements within it. So count was correct, it's just not giving me the number that I'm looking for.
Thus, I have three questions.
1) How do I count my elements correctly?
2) Could someone explain to me why this reads as 4 elements?
3) Is my array not multi-dimensional? (since both counts yield the same result of 4)
Best Regards and Thanks in advance,
Josh

Answer 1

`while($race[] = $query->fetch_object());`
$query->fetch_object() returns a null to indicate that there are no more entries in the dataset, but you're still assigning that null value to your $race array as a last entry, and only then allowing the while to terminate its loop.... that's why you have 4 entries in the array rather than 3.
Your array is not multidimensional, because the entities stored in the $races array are objects, not arrays; it would only be multi-dimensional if it was an array of arrays

Answer 2

The reason is actually pretty straight forward. When inserting data into your array using while($race[] = $query->fetch_object()) you always insert the final $query->fetch_object() which is gonna be equal to null. That is when you exit your while loop. Thus, your array's last item will always be null, just like in your own var_dump.
One way to fix this would simply to subtract 1 from your result. Another way would be to implement inserting like this:
$race = [];
while($row = $query->fetch_object()) {
array_push($race , $row);
}
The best way to count however would be by simply executing an SQL COUNT command:
$query = $conn->query("SELECT COUNT(DISTINCT Race) FROM Races");

Answer 3

Your php count is returning the amount of fields on your result object, not the amount of rows.
Try this for your SQL query:
$query = $conn->query("SELECT COUNT(DISTINCT Race) FROM Races");
Should you wish to use the same query as you have now, try:
$raceCount = $query->num_rows;