field

The field from the datasource to which the column is bound. If you have inner objects into your datasource you can bind the column to such inner property by using compound key syntax.

$("#grid").shieldGrid({
    dataSource: {
        data: [
            { ID: 1, name: { first: "first1", second: "second1"} },
            { ID: 2, name: { first: "first2", second: "second2"} }
        ]
    },
    columns: [
        { field: "ID" },
        { field: "name.first" }
        { field: "['name']['first']" }
    ]
});

Online example you can find here: foreign key fields