[Israel.pm] unshift vs push&reverse

Avishalom Shalit avishalom at gmail.com
Thu Mar 26 02:44:27 PDT 2009


thanks gabor, that was very insightful
(i was about to suggest running two loops and testing them, but i must
agree that that the effort is in the wrong direction.)
---

Besides the only place on Earth where a queue is implemented
with unshift is Israel. "Just asking a question".
:-D :-D






2009/3/26 Gabor Szabo <szabgab at gmail.com>:
> On Thu, Mar 26, 2009 at 11:13 AM, Berler Chanan <chananb at centerity.com> wrote:
>> Hi All,
>>
>> I have a set of SQL needed to be run using timestamp field.
>> I have created an array and needs to push / unshift the SQL statements into
>> it for future execution
>> (different conditions builds different set of SQL statements).
>>
>> I am using unshift to push  the values into an array, so I will have the
>> correct order, but I wonder
>> if it is best to use push and reverse functions instead.
>>
>> Can anyone direct me to performance of unshift vs. push&reverse ? or
>> push&pop ?
>> Thanks
>> Chanan
>>
>
> Why do you care?
> Please answer the following questions in order:
>
> Does your code do what it has to do?
> Is the code clear to your satisfaction?
> Is there a performance issue ?
> Have you profiled the code checking where is the performance issue?
> Is the performance issue in the code that adds the SQL statements.
>
> Then ask the above question.
>
> BTW You are writing "I am using unshift to push  the values" which
> would indicate
> me that you are using the incorrect method. If you talk about pushing
> values then
> use that keyword it makes much more sense.
>
> Besides the only place on Earth where a queue is implemented
> with unshift is Israel. "Just asking a question".
> (ok, not really)
>
> Gabor
> ps. push should be way faster than unshift but I am quite sure it does not
> matter in your code. If you want to check, benchmark them.
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-- 
-- vish


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