Re: Refining query statement - Mailing list pgsql-general

From Adrian Klaver
Subject Re: Refining query statement
Date
Msg-id cf026bdf-f68e-f17f-0ab7-b7fb53a5b8bd@aklaver.com
Whole thread Raw
In response to Re: Refining query statement  (Ron <ronljohnsonjr@gmail.com>)
Responses Re: Refining query statement  (Thomas Kellerer <spam_eater@gmx.net>)
List pgsql-general
On 1/15/19 8:02 AM, Ron wrote:

>> the best way to do it:
>>
>> So we end up with something like this:
>>
>>      select distinct on (C.contact_id) C.contact_id, C.lname, C.fname, 
>> C.direct_phone, O.org_name, A.next_contact
>>      from Contacts as C
>>        join Organizations as O on C.org_id = O.org_id
>>        join Activities as A on C.contact_id = A.contact_id
>>      where A.next_contact <= 'today'
>>        and A.next_contact > '2018-12-31'
>>      order by c.contact_id, a.next_contact DESC;
> 
> And I've never liked this method (though I'm old and crotchety)....
> 

What is the specific objection?

To me:

1) Plus side. It saves an explicit sub-query

2) Minus side. It is not portable. But then complete portability is a 
unicorn in my opinion.

-- 
Adrian Klaver
adrian.klaver@aklaver.com


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