Make a second form with whatever options you'd like to filter on, this part will be specific to your data but you want something like
<form id="search-form">
<label>Name:</label><input type="text" name="patient-name"></input>
</form>
You'll need to build a query string (and make sure you use GET, because that will make things easier for you). This will require tweaking if you want to use radio buttons, or something similar, but here's the general idea:
function getSearchParameters () {
var form = document.getElementById('search-form');
var inputs = form.getElementsByTagName('input');
var result = '';
var i;
for (i = 0; i < inputs.length; i++) {
if (inputs[i].value) {
result += "&" + inputs[i].name + "=" + inputs[i].value;
}
}
return result;
}
In the onClick handler for your patient data links, you'll call this function and append its result to your query string:
element.onclick = function () {
var patientDataUrl = '/patients.php?param1=someValue';
patientDataUrl += getQueryParameters();
/* then do your ajax stuff as normal */
};
Then on the server side, within patients.php simply check for the presence of the search fields i.e.
if(isset($_GET['patient-name'])) {
$patient_name = mysql_real_escape_string($_GET['patient-name']);
$query = "SELECT * FROM `patients` WHERE `patient_name`='$patient_name';";
} else {
$query = "SELECT * FROM `patients`;";
}
(make sure you sanitize the string!)
I'd recommend considering a JS framework to make your life much easier (for instance, jQuery would allow you to send this via POST or easily serialize it into a GET query string via .serialize()
)