How to configure an optional row delete?

arame

I have a table of trades, and I only want to delete a trade if there is no foreign key relationship with any other table. So if i trade is deletable I send back from the server the primary key for that trade; TradeId. If it is NOT deletable, I send instead zero. That part works.
So my datatable is defined in the following way;
[code]

Trade Maintenance
To edit a trade, double click on the trade name, edit it and press enter.






TradeName











$(document).ready(function () {
var element = $('#tradeList');

var serverDataSource = element.attr('data-server-data-source');
var updateUrl = element.attr('data-update-url');
var addUrl = element.attr('data-add-url');
var deleteUrl = element.attr('data-delete-url');

var otable = $('#tradeList').dataTable({
"bServerSide": true,
"sAjaxSource": serverDataSource,
"bProcessing": true,
"bLengthChange": false,
"iDisplayLength": "15",

"bPaginate": true,
"sPaginationType": "full_numbers",
"aoColumns": [
{
"sName": "ID",
"bSearchable": false,
"bSortable": false,
"bVisible": false
},
{ "sName": "TRADENAME" },
{
"sName": "TRADEID",
"bSearchable": false,
"bSortable": false,
"fnRender": function (oObj) {
// oObj.aData[2] returns the TradeId
var id = oObj.aData[2];
if (id > "0")
//return "Delete";
return "";
else
return "";
}
}
]
}).makeEditable({
sUpdateURL: updateUrl,
sAddURL: addUrl,
sDeleteURL: deleteUrl
});

function reloadTable() {
otable.fnDraw();
}

$('.dataTables_filter').attr("style", "float:left");
});
[/code]
I have at least 3 problems;
1/ I used the Jeditable library for updates. So where I return an empty string instead of a delete button, I get the text; "Click to Edit appear". I do not want this column to be editable and this appears.
2/ I can't get the onclick event to work, the callback function is not recognised
3/ Probably there is a better unobtrusive way of doing this?