Another date range join problem

Hi folks, me again.

I'm back with my availability and roster tables again.

I have:

Table "public.availability" Column   |            Type        
-----------+------------------------aid       | serial primary keyasid      | integer                asdate    | date
               afdate    | date                   
 
     Table "public.roster_staff"  Column    |  Type   |   Modifiers
-------------+---------+---------------rsdate      | date    | not nullrsgid       | integer |rsgsid      | integer
|rssid      | integer |
 


I want to do a join giving the details from the availability with a count of 
roster_staff records within the range asdate->afdate for each staff member 
(asid <-> rssid)

e.g.
availability

1    1    2007-04-01    2007-04-01
2    1    2007-04-10    2007-04-15

roster_staff

2007-04-01    4    5    1
2007-04-11    4    6    1
2007-04-13    4    3    1
2007-04-14    5    5    1
2007-04-15    5    6    1

giving

1    1    2007-04-01    2007-04-01    1
2    1    2007-04-10    2007-04-15    4

-- 
Gary Stainburn
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