php - Retrieve record ID after insert -

admittedly, bit out of league here, attempting project anyway.

background:
i developing page allow users enter data database. database has multiple tables have data inserted , updated. first action user takes select option drop down , click "create". clicking create button create record in 1 of tables. also, upon clicking "create" larger form displayed. once larger form complete, user can "save" work. planning on using update query allow user save work.
question:
using ajax post data (see example below), want return record id (primary key) page when visitor saves additional information, database knows record update.

//script

$(function(){   $('#create').click(function(event) {      event.preventdefault();       $.ajax({        type: "post",        url: "url",        data: {"optimizationtype": $("#optimizationtype").val()},         success: function(results){         $("#mvt-experimentdetails").css("display", "inline-block");         $("#create").attr('value', 'save');         $("#create").attr('id', 'save');          }      });    });  }); 

//php includes

$expid = mysqli_insert_id($con); 

know suppose return in success area of ajax, not sure how that...any appreciated.

on php side, after run insert, you'll want last_insert_id , echo that.

for example (using pdo , pseudocode):

insert table values (x,y) $id = $db->lastinsertid(); echo $id; 

on client side, let me recommend $.post instead of $.ajax - find easier use. however, theory same both.

$.post('url', {         data-key: data-value,         next-data-key: next-data-value     },      //now callback     function (recordid) {        //do recordid         alert(recordid); });