# ODataCollectionView and ODataVirtualCollectionView

The ODataCollectionView class provides a simple way to connect controls to OData sources. When you create an ODataCollectionView, it starts loading all the data in the source, given the filtering and paging constraints.

The wijmo.odata.ODataVirtualCollectionView extends ODataCollectionView to provide on-demand loading of data. The wijmo.odata.ODataVirtualCollectionView does not automatically load the data from the server. Instead, it relies on the setWindow method to load data fragments (windows) on demand.

The grids below show how both classes work. Notice how the grid on the left shows the data being loaded gradually. The grid on the right shows the full record count immediately, but the data will not be loaded until you scroll down.

### ODataCollectionView

ODataCollectionView: {{flexCV.itemsSource.items.length | number}} items

### ODataVirtualCollectionView

ODataVirtualCollectionView: {{flexVCV.itemsSource.items.length | number}} items