Oracle executives teased such an event during a private August gathering for local health care industry officials on the rooftop of a luxury downtown Nashville hotel. Now the company has set a date — sending a stronger signal of the potential role it sees Nashville playing to fuel its health care technology ambitions. Oracle has a lot on the line, just one year removed from the largest acquisition in its 45-year history — its $28.3 billion purchase of health tech company Cerner Corp. It's been two-and-a-half years since Oracle sealed a commitment to build an office campus on the East Bank of the Cumberland River, opposite Germantown and just north of downtown. Construction has yet to begin, but that doesn't mean Oracle isn't hiring. Far from it.