A poorly managed database table has grown to be enormous. 48+gigs of orphan records. I am trying to clean it up and put my dangerously full hard drive back to a normal state. I will be deleting approx 400 million records from this table. This is running as I type. I notice that I am not seeing any drop in my hard drive space but I am seeing the memory drop on system table queries, I am running to get table size. The database is using "Simple Recovery Model".

There are many questions similar to this with responses saying you need to shrink the database. But they go on to explain how bad/scary this is to do because of fragmented data etc. 


Since the database should not be this size. Is it still bad for me to shrink it?
This is a production database. If I shrink it will it cause downtime or lock the database?
In SQL Server Management Studio you have two options for shrink, database or files. Given my situation what would be the best option?
is there a rule on the percentage of free space a DB should have?


Even reading the tag description of shrink makes me not want to do it. Is there another way?


Question: Broker (AirTicket24) has changed part of flight, can i ask a full refund?
Answer: It's probably not the broker who changed the flight but the airline, which indeed has the right to cancel and/or reschedule flights. However it would seem that, according to the FAQ page from AirTicket24, you can ask for compensation in case of substantial changes:


  23. What happens if the airline changes its flights?
  
  The airlines are sometimes forced to modify the itineraries, hours and number of their flights. In this case we will try to inform you for any changes before the date of departure so that you adjust your program to these changes. These changes are usually of minor importance without significant impact on your trip. If significant changes occur related to your flight (for example change in departure time for more than 2 hours or change of departure airport) and you have no alternative that suits you then you can request compensation from the airline, according to the passenger's rights established by the European Union, unless you have been informed on time by the airline.


Hence I would go ahead and contact both your broker, quoting the FAQ, add well as your airline to see what can be arranged.