I wasn't talking about caching your db queries. I was talking about caching your connections to the database. Usually, opening a new connection to the database is very costly in terms of time. If you could have your application open up a bunch of connections to the database during application startup then you could just use those connections when you needed them. That's what I meant by a pool. When you need a connection, you take one from the pool, use it, then release it back to the pool (just don't close it).