Re: Fwd: Re: sum(bool)? - Mailing list pgsql-sql

From darcy@druid.net (D'Arcy J.M. Cain)
Subject Re: Fwd: Re: sum(bool)?
Date
Msg-id 20010225235403.2F8E81A62@druid.net
Whole thread Raw
In response to Fwd: Re: sum(bool)?  ("J.Fernando Moyano" <txinete@wanadoo.es>)
List pgsql-sql
Thus spake J.Fernando Moyano
> El Viernes 23 Febrero 2001 16:22, escribiste:
> > i want to add up the "true" values of a comparison like
> >
> > sum(a>b)
> >
> > it just doesn't work like this
> >
> > any workaround?
> 
> I did exactly the same thing two months ago ....
> 
> I created this tiny function:
> 
> CREATE FUNCTION bool2int(bool) RETURNS integer
>     AS 'select (case when $1=true then 1 else 0 end)'
>     LANGUAGE 'sql';
> 
> 
> You can do:  sum(bool2int(a>b))
> 
> easy ??? ;-))

Almost as easy as "SELECT COUNT(*) FROM table WHERE a > b"

-- 
D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves
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