Reading Data Warehouse Snapshot Schemas at https://jazz.net/wiki/bin/view/Main/DataWarehouseSnapshotSchemas20, in the section for Workitems Snapshot
The available Tables includes
Live_Workitem_Cnt
Type: Live table
Description: Information about one or more work items in the repository. This is a live view into the repository, and does not come from data stored in the data warehouse.


The confusing part is that it says This is a live view into the repository, and does not come from data stored in the data warehouse.

As the snapshot's description states: The work items snapshot collects both point-in-time and delta information about various aspects of the work items in the repository, so I guess it means it is a mix of static view and live tables.

What is the difference between using Live Snapshot and Live Tables in Work Item Snapshot in terms of performance concern?