@Override
	public Address getFirstPropertyAddress() {
		validate(lock);
		Table table = propertyTable;
		if (table == null) {
			return null;
		}
		try {
			AddressKeyIterator iter = new AddressKeyIterator(table, addrMap, true);
			return addrMap.decodeAddress(iter.next());
		}
		catch (NoSuchElementException e) {
			// ignore
		}
		catch (IOException e) {
			errHandler.dbError(e);
		}
		return null;
	}
Delete this property map and all underlying tables.
This method should be overidden if any table other than the 
default propertyTable is used.
@throws IOException if IO error occurs
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/properties/PropertyMapDB.java