Serious Count Rows Problem

[eluser]osci[/eluser]
Comsidering the placement I consider it rather simple.
First of all I didn't read only about AR in user_guide.
It's placement is under Database as is AR. You didn't have trouble finding about AR right?

About the other questions
count_all_results to be accurate with your AR query has to be supplied the same restrictions.

num_rows return the rows of the last query (last run)

Proper method depends on user likes I guess.