Fact Table Loads

Here is a scenario:

* Fact table contains 100 million records
* Monthly Load of 10million is done at the end of the month to the same fact table

In this scenario, how do you handle the indexes in fact table at the time of load?
If indexes are made unusable before load, then the rebuild index is time consuming after the load.

So, what strategy do you follow in such scenarios?

How do we ensure that the data is made available to the users in the shortest possible time. (Assume we could receive data only in the end of the month and should be made available the earliest in the fact table for detailed drilling purposes)

- Thanks,
bi_at_nj