If you have a scenario where you have multiple incoming DIDs pointing to the same queue, and want to track how many calls you received on the queue from each of those DIDs, the easiest thing to do is use the Area Analysis function of QueueMetrics to take care of this automatically.
When a call comes in, you add the DID code to the incoming Caller ID, so that you get incoming numbers like "D7-0123456" where D7 means the call was received on DID 7 and 0123456 is the original Caller-ID. Then if you go to the Area Analysis in QueueMetrics, you can ask for a call report based on a number of Caller-ID digits (like 2 in this case, to extract the first two characters of the caller), and it will break down all calls by DID code.
You may also use this same function to track other information associated with the same calls, like multiple IVR choices pointing to the same queue.
For more information on Caller-ID rewriting, see the FAQ entry "How to set the Caller-ID"
If you need a break down of calls by calling DID and time, see Tracking hourly call distribution for multiple incoming DIDs