Thanks for your responses.

Matthew, we do a one API call to insertRows() with the argument being a data.frame with 15K rows - this usually is the correct approach to avoid overhead associated with each function call. Is it not the case here?

Brian, I am running on PostgreSQL, yes, sorry forgot to mention that. And indeed it looks like I have not tweaked manually (m)any of the settings in the postgresql.conf file. Am I correct in assuming to look at the "RESOURCE USAGE" section? Any quick fixes or other suggestions from the pro about modifying these? (FYI, I currently have 8GB of RAM.)

Thanks.