join/group/count query.

Hi folks. I have the following query which works for me at the moment.
However, o_model refers to a table stock_models which has one record for each
model type. At the moment if I another record to the stock_models I have to
amend the select. Is it possible to make this automatic by joining the
stock_models data somehow?

select o_p_id as key, o_p_id as p_id, p_name, count(o_p_id) as total,
count (case when o_model = 5 then 1 else NULL end) as KA,
count (case when o_model = 10 then 1 else NULL end) as Focus,
count (case when o_model = 13 then 1 else NULL end) as C_Max,
count (case when o_model = 16 then 1 else NULL end) as S_Max,
count (case when o_model = 20 then 1 else NULL end) as Fiesta,
count (case when o_model = 25 then 1 else NULL end) as Fusion,
count (case when o_model = 30 then 1 else NULL end) as Mondeo,
count (case when o_model = 35 then 1 else NULL end) as Galaxy,
count (case when o_model = 40 then 1 else NULL end) as Ranger,
count (case when o_model = 50 then 1 else NULL end) as Connect,
count (case when o_model = 60 then 1 else NULL end) as Transit,
count (case when o_model = 70 then 1 else NULL end) as Fiesta_Van
from order_details
where date_trunc('month',CURRENT_DATE) = date_trunc('month',o_ord_date)
group by o_p_id, p_name;
--
Gary Stainburn

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