[redland-dev] order by on dates

[Gregory Williams]

On Jun 7, 2005, at 12:56 PM, Danny Ayers wrote:

> On 6/7/05, Dave Beckett <dave.beckett at bristol.ac.uk> wrote:
>
>> I guess you'll be happy to know that I added an initial sorting
>> implementation in the query engine CVS this morning.
>
> Bravo!

I wholeheartedly second this "Bravo!" I'm very excited by this news.

>> Sorting is performed on all results in memory (so don't try that  
>> with huge results)
>> and it's with stringy compares so integer 10 collates less
>> than integer 2 since "10" < "2", i.e. like RDQL.  Fixing that is
>> piles of detail.   So date sorting might work if you stick to
>> a normalised form such as without timezones.

FWIW, This doesn't bother me much. My biggest issue was having  
sorting take place at the rasqal level before the data crossed the  
language-binding barrier. After that barrier was crossed, the size of  
the nodes (when wrapped in [perl] objects) and the multiple calls  
back into the API to retrieve data from those nodes made sorting  
*extremely* inefficient. At some point I'd like a "full" sorting, but  
as long as rasqal is doing a first-pass, I can hand off the data to a  
sorting algorithm that will hopefully approach O(n) (to handle the  
timezones, &c.).

thanks again, Dave!

.greg

-- 
"Writing code on one line is like playing
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