I'm confused when looking at the database connection metrics for my AWS Relation Database Service (RDS) monitor. I see these different metrics reported:

• Database connection sum
  Sum of what? Over what time period?
• Database connection average
  Average of what? Over what time period?
• Database connection maximum
  Maximum of which metric (sum, average, real)? Over what period?
• Database connections real count
  I'm guess this is the number of actual connections at the time the poll is taken.

The other odd things is that the DB connections chart dataset labeled "Database connection Sum" actually matches with the raw datatable numbers with the column heading "Avg. DB Connections (count)." See attached image.

Can someone explain these different metrics. I'm missing some alarms because I can seem to figure which metric I should be monitor (and how often).