querying the data dictionary

I have two questions on this topic.
First if I query my user_tab_columns I have about 1062 column names. How do I query to figure out which one is used the most?

Second, if I query my all_users table I get a list of about 200 users created on different dates. How do I find out which one was created most recent (by date only)? I know I can do an order by created but I lose the the top of the list because it is too long to keep in the buffer. Isn't there an easier way?

Thanks for any help on this. Received on Sat Mar 30 2002 - 13:04:31 CST