I have done something similar before using factory functions see jsbin example for similar example to yours
var oTable = new sap.ui.table.Table({
title: "Table column and data binding",
showNoData : true,
columnHeaderHeight : 10,
visibleRowCount: 7
});
oTable.setModel(oModel);
oTable.bindColumns("/columns", function(sId, oContext) {
var sColumnId = oContext.getObject().columnId;
return new sap.ui.table.Column({
id : sColumnId,
label: sColumnId,
template: sColumnId,
sortProperty: sColumnId,
filterProperty: sColumnId
});
});
oTable.bindRows("/rows");
you could use 2 globally named models in this scenario, one for the metadata one for the data eg
sap.ui.getCore().setModel(oMetaModel, 'meta');
sap.ui.getCore().setModel(oDataModel, 'data');
..
oTable.bindColumns("meta>/columns" function...
oTable.bindRows("data>/rows");
Heres an example jsbin example of dynamic columns based on OData metadata