How to filter json encode array count?

Question

In my example I have a PHP script that, from AJAX, does a tally of everyone named 'Richard.' I would like to further modify this by counting the people named Richard, that match the age of some input value, as shown in $theirage .

Specifically, I would like to sum up the two ages, and only show the ones that equal 20 in my array. $row[age] corresponds to the value age in my DB, while $theirage is a user input.

At the end I want to only tally the summed ages that equal to 20, in this case.

    $theirage = $_GET['theirage'];
    $query = mysqli_query($con, "SELECT count(*) as cnt FROM members WHERE
    name = 'Richard'
    ");
    $row = mysqli_fetch_assoc($query);
    $bow = $row['age'] + $theirage;
    $if ($bow = 20){
    $person = $row['cnt'];} 

echo json_encode( array(
    'person' => $person
) );    

How might I go about this?

Answer 1

I suggest you query members table to count all who are matching your criteria: specific name 'Richard' and specific age $_GET['theirage'] :

<?php
$theirAge = $_GET['theirage'];

// This is important: since we're using $theirAge in query string, we need to escape it
$theirAge = mysqli_escape_string($theirAge);

// Let's query all members whose name is Richard and age is equal to $_GET['theirage']
$query = mysqli_query($con, "SELECT count(*) FROM members WHERE name = 'Richard' AND age + $theirAge = 20");

$row = $query->fetch_row();

$totalRichardsOfGivenAge = $row[0]; // here is your result.

// And now let's return JSON
echo json_encode($totalRichardsOfGivenAge)