Filters in Business Objects

It keeps amazing me just how many types of filters there are in Business Objects.

• First : there are the Query filters. The most limiting filters, which have an effect on the datacube - everyone knows (I hope) about these filters, and uses them. They depend a lot on the database and have a big influence on the speed of the report (depending on indexing in the database).
• Second : there is the report-filter. Few documented, easy to use, a filter set on a report only applies on the report and on all tables in it, but not on the other reports.
• Third : the table-filters. Commonly used to filter inside a table, each table in a report can have its own filters. (first and second can be found in Format>Filters

These are the ones you see in a basic BO class (2 days) and continue with in the advanced class (1 day) But there is a fourth (little known) way to filter, and I found it most useful in some situations.

That fourth filter is what I would call : the object-filter -- it means that you can filter out a certain object based on a given condition. How :

In the properties of a table, a chart, a section and some other stuff, you can activate the "Hide Block" checkbox. If you do so, and confirm with ok, then the block is gone, and you can only get it back if you switch BO into structure view (View > Structure) -- so don't do that. But you might have asked yourself.. what is that box underneath ? well, here you can enter a condition - but you have to enter it manually in this format : =function(<object>) operator value. e.g. =Sum(<sales>) < 8000000

The result of the comparison has to be a boolean value (true/false). e.g. on a chart you could count how many years you have available and only show the chart if you had more than 1 year. e.g. =count(<year>) > 1. The chart will remain hidden as long as you don't have more than 1 year. When you refresh and an extra year was added to the result of the query, then the chart would show up. Pretty nice trick.