Re: Generating Rows from a date and a duration

Hi Brian, Hi List,

At Sat, 4 Sep 2010 09:20:53 -0400,
Brian Sherwood wrote:

> On Fri, Sep 3, 2010 at 5:40 AM, Tim Schumacher <
> tim(dot)daniel(dot)schumacher(at)gmail(dot)com> wrote:
>
> > I'm kinda stuck situation, I have a timestamp which resambles a
> > startdate and a duration in days and I want to bloat this, so I have a
> > row for every day beginning from the startdate. I have created an
> > example bellow, maybe I'm doing it on the wrong angle and you can come
> > up with some better ideas:
> >
> > BEGIN TRANSACTION;
> >
> > CREATE TABLE example
> > (
> > id serial NOT NULL,
> > startdate timestamp without time zone,
> > duration int_unsigned NOT NULL,
> > CONSTRAINT pq_example_id PRIMARY KEY (id)
> > ) WITH (OIDS=FALSE)
> > ;
> >
> > insert into example(id,startdate,duration) values (1,'2010-09-03',4);
> > insert into example(id,startdate,duration) values (2,'2010-09-03',6);
> >
> > CREATE OR REPLACE FUNCTION bloat_duration(IN id integer,
> > IN startdate timestamp
> > without time zone,
> > IN duration integer,
> > OUT id integer,
> > OUT duration_date date)
> > RETURNS SETOF RECORD AS
> > $$
> > BEGIN
> > RETURN QUERY SELECT
> > id,to_date(to_char(startdate,'YYYY-MM-DD'),'YYYY-MM-DD')+s.a AS
> > stockdate FROM generate_series(0,duration-1) AS s(a);
> > END;
> > $$
> > LANGUAGE 'plpgsql';
> >
> > -- This works, but not what I want
> > SELECT * FROM bloat_duration(1,'2010-09-03',4);
> >
> > -- This does not work
> >
> > SELECT * FROM example AS ex
> > INNER JOIN bloat_duration(ex.id,ex.startdate,ex.duration) AS bd ON bd.id
> > = ex.id
> >
> > ROLLBACK TRANSACTION;

> Take a look at the generate_series function in the "set returning functions"
> section of the manual.
> http://www.postgresql.org/docs/8.4/interactive/functions-srf.html

As you can see in my example, I'm already using it and this is my
dilemma. Since I can not bring the values of the FROM-Table to the
parameters of my function.

Greetings

Tim

--
Compassion -- that's the one things no machine ever had. Maybe it's
the one thing that keeps men ahead of them.
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