There is a standard boolean on the incident object called isbreached which will tell you if an incident has breached and another attribute called create date which will tell you when the incident was created. If you write a query using those criteria and splash a few other attributes about, you should have what you need.
Thanks for the reply..
if I use create date, it will display the incidents created within that period, but my client is looikng only for those tickets which were breached in the given period regardless when they were created....
OK - start your query at the Incident/Escalation object instead and look for the expiry date as the item to use on your criteria. You can still get to the incident fields too, but if you start with Expiriy your date will then be the one you are after. I'd still use the isbreached flag on the incident as the other filter to indicate if the incident has breached.
In your original post you mentioned extracting from the database. If so, you might find the document on this link useful. It covers the main tables that hold escalation and assignment information.
This is how we do ours...
From Incident, Incident
AND Assignments.Incident.Is Breached Is Equal to (True)