no need to sort by a <i>non existing</i> key, all you need is that the BY pattern does not contain an asterisk, so it is constant, that means all the elements have the same value for sorting, and Redis knows that it can skip it and use the List natural ordering.<p>It is interesting that you can ask for single elements of an hash, like in: GET object:*->field<p>With 2.6 and scripting this kind of optimizations will become the rule.
this assume you're connecting to <i>one</i> redis server and not running a cluster of redis servers, or have tagged the keys being requested in a cluster of redis servers