This could be a bug with VirtualCenter. However, before raising flag, I would recommend you to check if all the VM's in your environment are installed with VMware Tools and updated to the latest version.
I dont thing there is anything wrong wity your database connectivity. Well why wouldn't this be a DB connectivity then? Bad data does not dictate a program error, programs should control the data, not the other way around. I don't care how far out of date VM tools are or how far the VM's are behind in version, VC should not disconnect because of an invalid query, period.
So this definitely points to connectivity, bad data should NOT drop the connection. It will ignore a null or unexpected data and move on, it shouldn't cause VC to simply disconnect. If VC crashes it wouldn't even log it (since if they didn't anticipated bad data, they certainly wouldn't handled exception errors either) and / or VC wouldn't restart. The fact that VC reports the Database is dropping concludes that the connection timed out (it's pretty forgiving) and there is something seriously wrong with the connection between VC server and DB. Which is yet ANOTHER reason I don't support running VC in a VM there are too many variables for this type of thing, connections are too inconsistent, but that's a forum for another day.
Bottom line is there IS a connection problem, data won't cause VC to drop it's connection VC handles the error and is saying exactly what is going on, loss of communication and query disruption.
This is ODBC, it's passing a parameter to the Oracle DB which it doesn't like, causing the Database (not VC) to disconnect the query, hence dropping the connection, so the query is dropping the connection.
ORA-01483: invalid length for DATE or NUMBER bind variable
Cause: A bind variable of type DATE or NUMBER is too long.
Action: Check your Oracle operating system-specific documentation for the maximum allowable lengt