Hi Christian, Thank you for your quick response and implementation. Very impressive. I will try to run some tests soon, if I find anything strange I will let you know. Daniël On Thu, Aug 14, 2014 at 8:36 PM, Christian Grün <christian.gruen@gmail.com> wrote:

Good evening Daniël,

I have introduced the suggested optimization, considering some more cases like $p = (1 to 10), $p >= 1 and $p <= 3 etc. I would be pleased if you could check out the latest snapshot and do some testing.

Christian

[1] http://files.basex.org/releases/latest/

On Thu, Aug 14, 2014 at 9:11 AM, Daniël Knippers <dknippers@gmail.com> wrote:

...

Good morning,

I wondered if there is room for optimization during the compilation of the following query:

let $oneBillion := 1000000000 for $x at $p in (1 to $oneBillion ) where $p = 1 return $x

I would have expected this to be compiled into something like

for $x in (1 to $oneBillion)[1] return $x

Or simply

(1 to $oneBillion)[1]

Judging only from the execution times of the original query versus the optimized ones, it seems the sequence of 1 to one billion is entirely generated, which seems suboptimal in this case.

Kind regards, Daniël Knippers