jquery - On dataTable scroll data should load from server side and append to existing records -

using node js , bootstrap developing web application . have table implemented using data table. performing search , sort using server side code . fetching 50 records. these working fine.

now want load data (next 50 records ) server side when scroll reached bottom.

currently code ,

$('#table-goal').datatable({         "fninitcomplete" : function() {             $('.datatables_scrollbody').mcustomscrollbar({                 theme : "dark-3",                 callbacks : {                     whilescrolling : function() {                         //alert("scroll");                         if (this.mcs.toppct == 100) {                             // need load data using same ajax , append data previous 50 records.                         }                     }                 }             });         },         "scrolly" : "230px",         "scrollcollapse" : true,         "paging" : false,         "info" : false,         "processing" : true,         "serverside" : true,         "ajax" : {             "url" : "/list/goals/suggestion",             "type" : "post",             "data" : function(d) {                 var custom = {};                 custom.columnlength = d.columns.length;                 custom.ordercolumn = d.order[0].column;                 custom.orderdir = d.order[0].dir;                 d.type = "goal";                 d.custom = custom;                 //d.limit = limit;                 //d.offset = offset;             }         },         "bautowidth" : true,         "columns" : [{             "data" : "name"         }, {             "data" : "flag"         }, {             "data" : "goal_id"         }],         "columndefs" : [{             "render" : function(data, type, row) {                 return '<div class="goal_name" data-name="' + data + '"><span>' + row.name + '</span></div>';             },             "targets" : 0,         }, {             "render" : function(data, type, row) {                 if (data == 'yes') {                     return '<div class="review-editable keywords text-center" data-type="goal"><span class="top-adjust"><img class="friend-icon" src="/images/target/friends.png"></span></div>';                 } else {                     return '<div class="review-editable keywords text-center" data-type="goal"></div>';                 }              },             "orderable" : false,             "targets" : 1         }, {             "render" : function(data, type, row) {                 if (data == null) {                     data = '';                 }                 return '<div class="text-center add-near-data"><span class="list-view"> <a class="btn-circle-add"> <img src="/images/target/add.png"> </a></span></div>';             },             "targets" : 2         }],         "order" : [[0, "asc"]]     }); 

and backend code

router.post('/list/goals/suggestion', function(req, res) { var reqdata = req.body; var sess = req.session; var id = sess.userid;   var columncount = reqdata["custom"].columnlength; var ordercolumn = reqdata["custom"].ordercolumn; var orderdir = reqdata["custom"].orderdir; var getsearchvalue = reqdata["search"].value; if (getsearchvalue == undefined) {     getsearchvalue = ''; } /* * paging */ var slimit = ""; if (req.body.start != '-1' && req.body.length != '-1') {     var slimit = " limit " + req.body.length + " offset " + req.body.start; } else {     var slimit = " limit  50  offset 0 "; }  /* * ordering */  if (columncount > 0) {     console.log('---------');     var sorder = "order  ";     (var = 0; < columncount; i++) {         if (ordercolumn == i) {             sorder += reqdata["columns"][i].data + " " + orderdir + ", ";         }     }     sorder = sorder.slice(0, -2);     if (sorder == "order by") {         sorder = "";     } }  /* * filtering */ var swhere = ""; if (getsearchvalue != "") {     getsearchvalue = getsearchvalue.touppercase();     var swhere = "where (";     (var = 0; < columncount; i++) {         swhere += "upper(name) '%" + getsearchvalue + "%' or ";     }     swhere = swhere.slice(0, -3);     swhere += ')'; }  var squery = "select g.goal_id,name,flag goal g left join (select distinct on (goal_id)  goal_id,flag user_goal_assoc ug left join (select 'yes' flag,(case when party_id = '" + id + "'  party_friend_id else party_id end) friend_id friend (party_id = '" + id + "' or party_friend_id = '" + id + "') , status = 1) fr on (fr.friend_id =ug.creater_id ,  creater_id != '" + id + "' , status = 1)) ug on ( g.goal_id = ug.goal_id) " + swhere + " " + sorder + " " + slimit;   client.query(squery, function(err, goallist) {     //console.log(goallist.rows);     var obj = {         "draw" : req.body.draw,         "data" : goallist.rows     };      res.send(obj); });}); 

i tried few logics didn't worked me. code how have proceed.

i know old post, see: https://datatables.net/extensions/scroller/examples/initialisation/server-side_processing.html

from can see should have add:

    scroller: {         loadingindicator: true     } 

to .datatable({ init.