Function Connection.lastCommandID
This gets incremented every time a command is issued or results are purged,
so a ResultRange can tell whether it's been invalidated.
Prototype
ulong lastCommandID() pure nothrow @property const;
This gets incremented every time a command is issued or results are purged,
so a ResultRange can tell whether it's been invalidated.
ulong lastCommandID() pure nothrow @property const;