ls will
have the effects to watch for changes starting from the call, up to the
moment EXEC is called.<br/><br/>When EXEC is called, either if it will fail or succeed, all keys are
UNWATCHed. Also when a client connection is closed, everything gets
UNWATCHed.<br/><br/>It is also possible to use the UNWATCH command (without arguments) in order
to flush all the watched keys. Sometimes this is useful as we
optimistically lock a few keys, since possibly we need to perform a transaction
to alter those keys, but 