Hi @WorldWillRock
Would be nice if we had a bit more information about the environment. Firewall usually are blamed but not always is guilt.
Some points you need to verify:
Look at ASDM logs and make sure not is being denied on this flow.
Make sure firewall interfaces, connection to switch and switch ports is not overload.
Make tests with ping between client and database and see how long packets take. Use different packets sizes on ping.
-If I helped you somehow, please, rate it as useful.-