interesting SQL database usage queries

Question

I am trying to generate some comprehensive information about my databases compile a list of interesting queries for database usage.

There is a log table with

date  
username  
servertime  
clienttime  
user query

as well as other tables that actually hold the query-able information.

Edit (for constructive subjectivity): What is the most interesting usage stats query for the provided information?

Some examples I have so far:

• Users per day,
• Queries per day
• Average query time per user

One suggestion per answer please; let me know if you want more information to work with.

Thanks!

Answer 1

Personally I'd be most interested in the top ten slowest queries.

Answer 2

Users that use the most CPU time and/or run the most intensive queries.