I'm thinking about ways to implement this but don't instinctively know the best route in Craft.
Our infrastructure is in AWS and, due to other applications, we have access to a read-replica DB instance alongside the master instance. I'm wondering about how to write an extension/plugin that would direct all
SELECT requests to either the master OR the slave, and all
INSERT / UPDATE / DELETE requests to the master only.
What are some possible paths for incorporating this?