Re: CASE Select, referring to selected value - Mailing list pgsql-sql

From Achilleus Mantzios
Subject Re: CASE Select, referring to selected value
Date
Msg-id Pine.LNX.4.44.0207021516290.7811-100000@matrix.gatewaynet.com
Whole thread Raw
In response to CASE Select, referring to selected value  ("Nick Riemondi" <nick@outerscape.net>)
Responses Re: CASE Select, referring to selected value  ("Nick Riemondi" <nick@outerscape.net>)
List pgsql-sql
On Mon, 1 Jul 2002, Nick Riemondi wrote:

Just rewrite your case statement in the where clause.

> Hi!
> I've got 2 date fields in table which constitute a term.  On select I'm
> calculating that term, BUT I can't figure out how to refer to it in the
> sql - or if it's possible.  I'd like to be able to use the case returned
> value for order, comparing, etc.  Here's an example:
> 
> select case when (current_date > available) then ((end_date -
> current_date) / 30) 
>             when (current_date < available) then ((end_date - available) /
> 30)
>        end
>        from listing
> 
> This yields something along the line of:
> 
>  case
> ------
>     2
>    39
>    11
>    64
> ...
> 
> which is great.  Now, I'd like to be able to do this for example:
> 
> select case when (current_date > available) then ((end_date -
> current_date) / 30) 
>             when (current_date < available) then ((end_date - available) /
> 30)
>        end
>        from listing
>        where case > 4
> 
> which yields:
> ERROR:  parser: parse error at or near ">"
> 
> Does anyone know how I could accomplish this?
> 
> Thanks in Advance!
> Nick
> 
> 
> 
> 
> 
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-- 
Achilleus Mantzios
S/W Engineer
IT dept
Dynacom Tankers Mngmt
tel:    +30-10-8981112
fax:    +30-10-8981877
email:  achill@matrix.gatewaynet.com       mantzios@softlab.ece.ntua.gr





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