Let's say that there is JNDI configured on the Worker and that JNDI is then used in a DB connection configuration in a graph. If the default read-only state of the connections created by the JNDI pool is set to true, the graph can create a read-only connection, for instance, when the first DB component in the graph is DatabaseReader. If DatabaseReader is followed by DatabaseWriter, it will re-use the connection from the pool. However, since the connection was created as read-only it would error out with the message saying: "ERROR: cannot execute INSERT in a read-only transaction". This can be resolved by explicitely declaring the defaultReadOnly property in the Worker JNDI definition and setting it to false. We might want to add this as a tip in our documentation.