what does a tool like Jasper Reports/report generator gives me?

Question

Ok, So I have to generate very complex reports from my DB.
If I am to do it with SQL the query themselves will be complex, and I will have to do some more manipulation on the results later, code level.
How do libraries like Jasper Reports/ Crystal Reports and friends save me time when developing such reports?
What will they give me?

Answer 1

These tools may not necessarily save you that much time writing the SQL, but they will give you a nice clean presentation of the data for your customers.