a) By giving filters and conditions in the report level.
b) OVERFLOW occurs when a calculation returns a value that is too large for Web
Intelligence to handle.
c) Select the properties at the report level and choose appearance from the tab. You
can adjust the tables horizontally and vertically.
d) When you have huge number of rows in report then u will get partial results in
that report.
For that you have to increase the (Limit Size of the Results) check box button in
Universe Parameters. Then your report will not overflows.