A value used to identify a column in a data array. Can be string if the data option contains an array of objects or an integer if the data option is an array of arrays.
$(function () {
// Get value
var returnsValue; // Type: any
returnsValue = $(".selector").wijfilter("option", "dataKey");
// Set value
var newValue; // Type: any
$(".selector").wijfilter("option", "dataKey", newValue);
});