If you don't recognise any of this code then you can't have really used
SPARQL with Jena before, try reading the SPARQL Tutorial -
http://jena.apache.org/tutorials/sparql.html

Rob

On 26/11/2013 08:34, "Dave Reynolds" <[email protected]> wrote:

>Use an IDE.
>Dave
>
>On 26/11/13 07:16, Maria Jackson wrote:
>> Thanks a lot for the help.
>>
>> Can you please tell me the name of the file where I can find these
>> functions?
>>
>>
>> On Mon, Nov 25, 2013 at 8:40 PM, Andy Seaborne <[email protected]> wrote:
>>
>>> On 25/11/13 14:23, Rob Vesse wrote:
>>>
>>>> Maria
>>>>
>>>> Yes you can do this, in ARQ the iterator which backs the ResultSet or
>>>> Iterator<Triple> returned from the appropriate QueryExecution.execX()
>>>> calls represents the plan and iterating over it causes the actual
>>>> execution to occur and is thus the execution time I.e.
>>>>
>>>> // Assume we have a query and a dataset ready to go
>>>> QueryExecution qe = QueryExecutionFactory.create(query, dataset);
>>>>
>>>> // Starting to execute the query only actually triggers plan
>>>>calculation
>>>> // Time around this to get the plan compilation time
>>>> ResultSet results = qe.execSelect();
>>>>
>>>> // Iterating the results actually executes the query
>>>> // Time around the while loop to get execution time
>>>> while (results.hasNext() {
>>>>     results.next();
>>>> }
>>>>
>>>
>>> That's the best there is.  It's not as clear cut as completely separate
>>> plan and execute stages. Only the high-level optimizations are
>>>measurable -
>>> TDB specific low level optimizations happen during execution.
>>>
>>> The major cost for TDB is whether the file caches are hot or cold.
>>>
>>>          Andy
>>>
>>>
>>>
>>>> Rob
>>>>
>>>> p.s. Please DO NOT email/CC developers with your question as well as
>>>> posting to the list or re-post your question multiple times,
>>>>developers
>>>> are all volunteers and will answer your questions as and when they
>>>>have
>>>> the spare time.  Also as Andy points out people are in potentially
>>>>vastly
>>>> difference timezones to you so you should always allow at least 24
>>>>hours
>>>> for a response if not longer.
>>>>
>>>> Emailing people directly as well as the list or multiple posting only
>>>> serves to annoy people and actually reduces the chance that people
>>>>will
>>>> respond to your questions.  It also subverts the purpose of the list
>>>>which
>>>> is to allow any knowledgeable user the chance to respond and share
>>>>their
>>>> knowledge with the wider community.
>>>>
>>>> On 25/11/2013 08:08, "Maria Jackson" <[email protected]>
>>>>wrote:
>>>>
>>>>   I need to know these query times as I am benchmarking Jena TDB
>>>>against
>>>>> postgreSQL. With postgresql I am able to separately retrieve the
>>>>>query
>>>>> execution time after the plan has been generated by postgresql using
>>>>> \timing. It would be great if Jena could  also give me the time it
>>>>>takes
>>>>> to
>>>>> retrieve the results after the plan has been generated separately by
>>>>>Jena
>>>>> as that would help me take a one to one comparison.
>>>>>
>>>>> I'll be really greatful to you for the guidance.
>>>>>
>>>>>
>>>>> On Mon, Nov 25, 2013 at 5:48 AM, Maria Jackson
>>>>> <[email protected]>wrote:
>>>>>
>>>>>   One can find time of query execution in Jena from tdbquery using
>>>>>--time.
>>>>>> But does this --time include the plan generation time. If yes, is it
>>>>>> possible to find:
>>>>>>    (plan generation time) and (time to retrieve the results after
>>>>>>the
>>>>>> plan
>>>>>> has been generated separately in Jena)?
>>>>>>
>>>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>
>




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