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 key
asid | integer
asdate | date
afdate | date

Table "public.roster_staff"
Column | Type | Modifiers
-------------+---------+---------------
rsdate | date | not null
rsgid | 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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