PHP count some rows - php

Question

I have a problem, I want to create a function which counts the data from the Database. But I want that from the column to count some ID's and not all rows.
My code that doesn't work:
function countMember() {
include("./config/config.php");
$fetch_countMember = $fetch_countMember->prepare("SELECT * FROM `accounts`");
$fetch_countMember->execute();
while($fetch_countMember= $fetch_countMember->fetch()) {
if($fetch_countMember["member"] == 5 || $fetch_countMember["member"] == 6 || $fetch_countMember["member"] == 12 || $fetch_countMember["member"] == 13 || $fetch_countMember["member"] == 14 || $fetch_countMember["member"] == 15 || $fetch_countMember["member"] == 16 || $fetch_countMember["member"] == 17 || $fetch_countMember["member"] == 20 || $fetch_countMember["member"] == 21)
$c_member++;
}
return $c_member;
}

Answer 1

You need to use PDO::exec()
elegant way to do it:
$pdo = new PDO(....);
$ids = [5,6,12,13,14,15,16,17,20,21];
$query = sprintf("SELECT * FROM accounts WHERE member IN (%s)", implode($ids, ','));
$count = $pdo->exec();
echo $count;