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From:Richard Date:April 8 2008 4:01pm
Subject:Re: Help with ORDER BY using two colomns [ solved thankyou :) ]
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Thanks,

This is for the unanswered list of questions, so the output list (not 
the list stored in the mysql database) should never go over 100.

by scalable, do you mean alot of ressources being used or a long wait 
for the answer? Because I belive I Could just use a simple limit if I 
needed to have a limited number of results on one page.

Every time a question is answered the update date will change, and the 
status could also change. So I don't see how to easily do this by 
creating another table.

Ben Clewett a écrit :
> Richard,
> 
> No problem, glad it works.  But note: this is not scalable.  If you have 
> more than a few hundred rows, you may want to think about a better 
> solution, like storing the order field permanetly and giving it an index :)
> 
> Ben
> 
> Richard wrote:
>> Thanks, it works like a charm :)
>>
>> Ben Clewett a écrit :
>>> A modification to my last email, try:
>>>
>>> SELECT
>>>   *, IF(update != '', update + 10, date) AS o
>>> FROM
>>>   my_table
>>> ORDER BY o DESC;
>>>
>>> +-----+------+--------+------+
>>> | num | date | update | o    |
>>> +-----+------+--------+------+
>>> |   5 |   40 |     90 |  100 |
>>> |   2 |   10 |     60 |   70 |
>>> |   6 |   50 |        |   50 |
>>> |   4 |   30 |        |   30 |
>>> |   3 |   20 |        |   20 |
>>> |   1 |    1 |        |    1 |
>>> +-----+------+--------+------+
>>>
>>>
>>> Richard wrote:
>>>> Thanks,
>>>>
>>>> I think that your solution will be sufficient for my needs, however 
>>>> I would still like to know for my personal knowledge how to manage 
>>>> correctly this kind of need.
>>>>
>>>> And to make it more complicated I've just rearlised that there is 
>>>> another element to take into account, I would need to add 10 days to 
>>>> the  update dates so they would place themselves in the correct 
>>>> position.
>>>>
>>>> This is how I need the system to work :
>>>>
>>>> Any new requests (without an update value) are ordered by date
>>>> I want to be able to answer these requests (adding a time stamp to 
>>>> the update field and if the customer does not answer within 10 days, 
>>>> to re insert them into the list.
>>>>
>>>> But as the update timestamp will be 10 days old, I would like to add 
>>>> 10 days to the update while inserting them to the list (not changing 
>>>> the actual value inserted in the database just add 10 days during 
>>>> the reordering process.). I hope my explanation in understadable ...
>>>>
>>>> :)
>>>>
>>>> Rafael Barbolo Lopes a écrit :
>>>>> Can't you do Something like:
>>>>>
>>>>> ORDER BY (update,date)
>>>>>
>>>>> The major column of ordering would be update and the second date.
>>>>>
>>>>> I'm not sure about this "solution"
>>>>>
>>>>> On Tue, Apr 8, 2008 at 8:54 AM, Richard <mysql_list@stripped 
>>>>> <mailto:mysql_list@stripped>> wrote:
>>>>>
>>>>>     Hello I've tried the following with mysql 4.1.11
>>>>>
>>>>>     SELECT * FROM quick_contact WHERE (`status` = '0') OR (`status`
> =
>>>>>     '2' AND `update` < '".(time()-864000)."') CASE WHEN `update` =
> ''
>>>>>     THEN ORDER BY `date` DESC ELSE ORDER BY `update` DESC END CASE;
>>>>>
>>>>>     It does not work but, is it my code that is wrong or is it just 
>>>>> that
>>>>>     case does not work with mysql 4.1.11 ?
>>>>>
>>>>>     Thanks :)
>>>>>
>>>>>     Kristian Myllymäki a écrit :
>>>>>
>>>>>         mysql version?
>>>>>
>>>>>         http://dev.mysql.com/doc/refman/5.0/en/case-statement.html
>>>>>
>>>>>         order by case when updated is not null then updated else 
>>>>> created
>>>>>         end desc;
>>>>>
>>>>>         /Kristian
>>>>>
>>>>>         On Tue, Apr 8, 2008 at 1:04 PM, Richard
> <mysql_list@stripped
>>>>>         <mailto:mysql_list@stripped>> wrote:
>>>>>
>>>>>             Hello,
>>>>>              I've got a table which containes two date colomns.
>>>>>              The first one is called `date` and the second `update`
>>>>>              In the first one I put the ticket creation date, and on
>>>>>             update I add or
>>>>>             change the update value.
>>>>>              So the update colomn does not contain a value until the
>>>>>             first update has
>>>>>             been done.
>>>>>              I would like to order the tickets by their last update
>>>>>             value. And if this
>>>>>             value does not exist use the date value.
>>>>>
>>>>>              at the moment I use this :
>>>>>
>>>>>              ORDER BY `date` DESC"
>>>>>              and I would like to replace it by something like this :
>>>>>
>>>>>              ORDER (IF `update`!= '' BY UPDATE ELSE BY DATE)
>>>>>
>>>>>              I know this code is completly wrong, just to try and
> show
>>>>>             you what I need
>>>>>             ...
>>>>>
>>>>>              Here is an example of what I want to achieve
>>>>>
>>>>>              num     |       date    |       update
>>>>>              -------------------------------------------
>>>>>              1       |       1       |
>>>>>              2       |       10      |       60
>>>>>              3       |       20      |
>>>>>              4       |       30      |
>>>>>              5       |       40      |       90
>>>>>              6       |       50      |
>>>>>
>>>>>              The required result would be :
>>>>>
>>>>>              num     |       date    |       update
>>>>>              -------------------------------------------
>>>>>              5       |       40      |       90
>>>>>              2       |       10      |       60
>>>>>              6       |       50      |
>>>>>              4       |       30      |
>>>>>              3       |       20      |
>>>>>              1       |       1       |
>>>>>
>>>>>              Thanks in advance :)
>>>>>
>>>>>              --
>>>>>              MySQL General Mailing List
>>>>>              For list archives: http://lists.mysql.com/mysql
>>>>>              To unsubscribe:               
>>>>> http://lists.mysql.com/mysql?unsub=1
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>     --     MySQL General Mailing List
>>>>>     For list archives: http://lists.mysql.com/mysql
>>>>>     To unsubscribe:    
>>>>> http://lists.mysql.com/mysql?unsub=1
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> -- 
>>>>> .:: Rafael Barbolo Lopes ::.
>>>>> http://barbolo.polinvencao.com/
>>>>
>>>>
>>>
>>
>>

Thread
Help with ORDER BY using two colomnsRichard8 Apr
  • Re: Help with ORDER BY using two colomnsKristian Myllymäki8 Apr
    • Re: Help with ORDER BY using two colomnsRichard8 Apr
      • Re: Help with ORDER BY using two colomnsRafael Barbolo Lopes8 Apr
        • Re: Help with ORDER BY using two colomnsRichard8 Apr
          • Re: Help with ORDER BY using two colomnsBen Clewett8 Apr
            • Re: Help with ORDER BY using two colomns [ solved thankyou :) ]Richard8 Apr
              • Re: Help with ORDER BY using two colomns [ solved thankyou :) ]Ben Clewett8 Apr
                • Re: Help with ORDER BY using two colomns [ solved thankyou :) ]Richard8 Apr
                  • Re: Help with ORDER BY using two colomns [ solved thankyou :) ]Andy Wallace8 Apr
                    • Re: Help with ORDER BY using two colomns [ solved thankyou :) ]Richard8 Apr
                  • Re: Help with ORDER BY using two colomns [ solved thankyou :) ]Ben Clewett8 Apr
      • Re: Help with ORDER BY using two colomnsTim McDaniel8 Apr
  • Re: Help with ORDER BY using two colomnsBen Clewett8 Apr