best way: diary functions.

Hi folks

I've got 2 tables, 

availabiliy
~~~~~~~

stdate    date
edate    date
workdays    integer
comments    text

example record
2007-03-01    2007-03-07     5    Please can I have alternate days


roster
~~~~
rdate    date
rdiag    varchar(10)

example
2007-03-01    B12
2007-03-03    B11
2006-03-05    B12
2007-03-07    B13

What would be the best way to create a view to list every date within a range 
giving either rostered, available but not rostered, and not available?

I've read through the docs and created a function (below) to return every date 
within a range, but I can't get my head round converting that to a query.

Although I'm doing this as a learning exercise, it will be used in a web site 
I'm developing so comments on speed and efficiency would also be welcome.

Gary

create or replace function date_range(fdate date,tdate date) returns setof 
date
AS $PROC$
DECLARE wdate date;
BEGIN return next fdate; wdate:=fdate+1; while wdate <= tdate LOOP   return next wdate;   wdate:=wdate+1; end LOOP;
return;
END;
$PROC$ LANGUAGE plpgsql;



-- 
Gary Stainburn
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