Re: Select .. Having vs computer fields

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От Antonio Fiol Bonnín
Тема Re: Select .. Having vs computer fields
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Msg-id 3C18CB35.8070209@w3ping.com
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Ответ на Re: Select .. Having vs computer fields  (Francisco Reyes <lists@natserv.com>)
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Francisco Reyes wrote:

>On Wed, 12 Dec 2001, Javier Dussaillant wrote:
>
>>At 12:54 PM 12/12/2001 -0500, Francisco Reyes wrote:
>>
>>>Can use use computed fields on the "having" part of select?
>>>I have tried:
>>>select a,b, count(*) as dups_count from some_table having dups_count > 1;
>>>
>>>and it gives me the error "Attribute 'dups_count' not found"
>>>
>>You have to GROUP BY in order to use HAVING. For example:
>>
>>SELECT a,b, count(*) as dups_count FROM some_table GROUP BY a,b HAVING
>>dups_count > 1;
>>
>
>My mistake for not including it in the example. I did use Group By.
>
Rewrite as

SELECT a,b, count(*) as dups_count FROM some_table GROUP BY a,b HAVING
count(*) > 1;


Antonio



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