momjian(at)svr1(dot)postgresql(dot)org (Bruce Momjian) writes:
> Re-add item with better description:
>> * Allow ORDER BY ... LIMIT 1 to select high/low value without sort or
>> index using a sequential scan for highest/lowest values
>>
>> Right now, if no index exists, ORDER BY ... LIMIT 1 requires we sort
>> all values to return the high/low value. Instead The idea is to do a
>> sequential scan to find the high/low value, thus avoiding the sort.
That's not much better, as it simply begs the question "why not use
MIN/MAX"?
I think the real point of Oleg's suggestion is a better way to do "top N"
queries. This does not get interesting unless N > 1.
regards, tom lane