Thread: ordering by multiple columns

<br /> Hi!<br /><br /> I'm trying to order a list in which the first parameter to order is a specific field, and the
secondshould vary depending on a specific condition. More explicit, I would like to do something like:<br /><br /> -
ORDERBY a.column1, [b.column2 if c.value != 19 || c.column2 if c.value==19]<br /><br /> That is to say, use a column if
avalue on each row isn't 19, OR use a different column if it isn't. How could I solve this? I've got to have a global
orderover my query, so I cannot separate it into two queries, etc :-? <br /><br /> Thank you!<br /><br /><br /> 

Pablo Barrón <amentoraz@gmail.com> schrieb:

> 
>  Hi!
> 
>  I'm trying to order a list in which the first parameter to order is a specific
> field, and the second should vary depending on a specific condition. More
> explicit, I would like to do something like:
> 
>  - ORDER BY a.column1, [b.column2 if c.value != 19 || c.column2 if c.value==19]
> 
>  That is to say, use a column if a value on each row isn't 19, OR use a
> different column if it isn't. How could I solve this? I've got to have a global

You can do something like this:

order by a.column1, case when c.value != 19 then b.column2 else c.column2 end;


*untested*, but the way is to use a case when <condition> then ... else
... end; - construct.


Andreas
-- 
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On 3/14/07, Pablo Barrón <amentoraz@gmail.com> wrote:
>  Hi!
>
>  I'm trying to order a list in which the first parameter to order is a
> specific field, and the second should vary depending on a specific
> condition. More explicit, I would like to do something like:
>
>  - ORDER BY a.column1, [b.column2 if c.value != 19 || c.column2 if
> c.value==19]
>
>  That is to say, use a column if a value on each row isn't 19, OR use a
> different column if it isn't. How could I solve this? I've got to have a
> global order over my query, so I cannot separate it into two queries, etc
> :-?
>
>  Thank you!

SELECT   (...)
ORDER BY a.column1, CASE          WHEN c.VALUE <> 19            THEN b.column2          ELSE c.column2        END;