When using slowlogs with the Amazon Relational Database Services (RDS) you want to truncate these tables once in a while.
Normally you can just do:
With RDS you'll get the following error message:
"Access denied for user '' to database 'mysql'"
This is because the user accounts don't have sufficient permissions to the system tables. Gladfully Amazon implemented a procedure which you can call with sufficient permissions to rotate and truncate the slow_log.