如何在JavaScript中每两秒执行一次PHP函数？

I have this PHP function called GetTotalItemsPercentage() which gets the amount of entries in my MySQL database and returns a percent based on the maximum amount of entries that are allowed (returns 50, 40, 39 etc.). However, I want this to update a div's height depending on this percentage. I currently have this code, however after the first update, it doesn't update again.

    <script type="text/javascript">
        setInterval(function() {
            $("#filled-jackpot-display").animate({height:'<?php include 'database/config.php'; include 'database/jackpot.php'; echo getPotFilledPercentage(); ?>%'});
        }, 2000);
    </script>

So how would I go about getting it to update every two seconds and constantly change the size of the div? I'm guessing I will have to run a loop in the PHP code and then use echo inside the PHP file to run JavaScript rather than the other way.

PHP executes on server, javaScript on the client, you have to make a new php file with

<?php include 'database/config.php'; include 'database/jackpot.php'; echo getPotFilledPercentage(); ?>

in it, let's call it 'getTotalIP.php' then you call it with ajax.

<script type="text/javascript">
    setInterval($.ajax('getTotalIP'), 2000); //Short answer with jQuery
</script>

If your script is intended to print something then you need more code to parse the answer. A good way to do it is printing the php result in json and parse it with javaScript.

Here you have more cross-browswer ajax information: http://www.w3schools.com/ajax/ajax_example.asp

You cannot execute PHP on the client side. The way to do this would be to call the php code with ajax() and then animate in the success handler

myscipt.php

<?php include 'database/config.php'; include 'database/jackpot.php'; echo getPotFilledPercentage(); ?>

myscript.js

setInterval( function() { 
    $.ajax({url: 'myscript.php', success: function(data){
       $("#filled-jackpot-display").animate({height: data});
}, 2000);

Note, since ajax is asynchronous, it may not smoothly animate in 2 second intervals. If you only need the height once, then load it on ready and proceed to animate in 2 second intervals