I get QVDs each month, the average size is about 370 MB. Currently, this is how I'm dealing with these files.
Concatenate all available QVDs generated on monthly basis to get one big QVD
Then, do Count/Aggregate functions and get result-set in a separate QVD
Link the resulting QVD to main data model
Is there a better way to handle this situation ? I'm more concerend about the size and the time it takes to execute. Should I go for incremental reload ?
Incremental reload is one of the best approach if your concern is size and execution time. Instead of concatinating all of your QVDs, you can use mapping load for tables with 2 fields. This will lessen the number of QVDs you have.