All replies agreed that the correct answer should be -21 (because one of the operands is negative). In this case, can we get our point back for today's breakfast? 🙂

Results for "index"portion are not reliable - they show multiple columns. Example:

table Reader with the following columns:

DeviceID, DoorTypeID, ReaderTypeID, DegradedMode, KeypadPresent, AntipassbackTime, GuestSignout, EgressAreaID, GuestSignin, AutoRelock, HasAssociatedOtisDEC, OEInterfaceID, OtisDECHostname, OEOperationModeID,...