Updating database without seriously screwing things up?

I've built apps in the past where in order to test things, I've had to manually issue SQL to the database and then try to read these changes via Hibernate. The problem is that an error is always thrown when I try to do this. I have a theory that EhCache is the culprit, but I'm not sure. Is there a setting I can enable to prevent things from getting messed up when being accessed from mu开发者_C百科ltiple applications?

Disable your second level cache when testing

<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>