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Hive, mail # user - Enhancing Query Join to speed up Query


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Naga Vijay 2013-06-13, 04:17
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Sanjay Subramanian 2013-06-13, 06:54
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Stephen Sprague 2013-06-13, 17:42
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Naga Vijay 2013-06-13, 18:31
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Re: Enhancing Query Join to speed up Query
Igor Tatarinov 2013-06-13, 22:29
I would expect no difference because of predicate pushdown.

igor
decide.com
On Thu, Jun 13, 2013 at 11:31 AM, Naga Vijay <[EMAIL PROTECTED]> wrote:

> Sure, Will do
>
>
> On Thu, Jun 13, 2013 at 10:42 AM, Stephen Sprague <[EMAIL PROTECTED]>wrote:
>
>> Hi naja,
>> test those two versions (or three now) and report back to the group.  :)
>> even if some smarty-pants thinks he knows the answer its always good to
>> confirm things are as they should be.
>>
>>
>> On Wed, Jun 12, 2013 at 11:54 PM, Sanjay Subramanian <
>> [EMAIL PROTECTED]> wrote:
>>
>>>  Hi
>>>
>>>  I would actually do it like this…so that the set on the left of JOIN
>>> becomes smaller
>>>
>>>  SELECT a.item_id, a.create_dt
>>> FROM
>>>      ( SELECT
>>>                     item_id, create_dt
>>>       FROM
>>>                     A
>>>       WHERE
>>>                    item_id = 'I001'
>>>        AND
>>>                   category_name = 'C001'
>>>       )  a
>>> JOIN
>>>          b
>>> ON
>>>         a.item_id = b.item_id
>>> ;
>>>
>>>
>>>   From: Naga Vijay <[EMAIL PROTECTED]>
>>> Reply-To: "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
>>> Date: Wednesday, June 12, 2013 9:17 PM
>>> To: "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
>>> Subject: Enhancing Query Join to speed up Query
>>>
>>>    Hi,
>>>
>>> Which of the two query options is better?
>>>
>>> SELECT a.item_id, a.create_dt
>>> FROM   a JOIN b
>>> ON     (a.item_id = b.item_id)
>>> WHERE  a.item_id = 'I001'
>>> AND    a.category_name = 'C001';
>>>
>>>  - or -
>>>
>>> SELECT a.item_id, a.create_dt
>>> FROM   a JOIN b
>>> ON     (a.item_id = b.item_id AND a.item_id = 'I001')
>>> WHERE  a.category_name = 'C001';
>>>
>>>  Thanks
>>>  Naga
>>>
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>>
>>
>
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Navis류승우 2013-06-14, 01:42
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Naga Vijay 2013-06-14, 04:35
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bharath vissapragada 2013-06-14, 05:08
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Alexander Pivovarov 2013-06-14, 05:45
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Naga Vijay 2013-06-16, 01:17
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Navis류승우 2013-06-16, 02:53