make view with union return one record

[Andy Colson <andy@xxxxxxxxxxxxxxx>]

I have gis data in layers, and a pin might appear in either layer, or 
both (parcelPoly, parcelPoint), or neither (and I dont care which I 
find)... so I have this view:


create view howardia.getPoint(shapeid, x, y, acres, pin, extent) as
  SELECT gid,
	st_x(st_centroid(the_geom)) AS x,
	st_y(st_centroid(the_geom)) AS y,
	acreage,
	county_pin,
	st_box2d(st_expand(the_geom, 100))
  FROM howardia.parcelPoly
 UNION ALL
  SELECT gid,
	st_x(the_geom) AS x,
	st_y(the_geom) AS y,
	acreage,
	county_pin,
	st_box2d(st_expand(the_geom, 100))
  FROM howardia.parcelPoint;

Which works fine for what I'm using.. it returns one or two records, and 
my code just takes the first record and runs with it.

but now... I'm adding something new, and having it return multiple 
records per pin is causing problems.  I tried adding a limit inside the 
view but then it never returns anything:

create view howardia.getPoint(shapeid, x, y, acres, pin, extent) as
select * from (
  SELECT gid,
	st_x(st_centroid(the_geom)) AS x,
	st_y(st_centroid(the_geom)) AS y,
	acreage,
	county_pin,
	st_box2d(st_expand(the_geom, 100))
  FROM howardia.parcelPoly
 UNION ALL
  SELECT gid,
	st_x(the_geom) AS x,
	st_y(the_geom) AS y,
	acreage,
	county_pin,
	st_box2d(st_expand(the_geom, 100))
  FROM howardia.parcelPoint
) as x limit 1;

I dont think I can put the limit outside the view, because the "new 
stuff" is going to select multiple parcels like:

select * from getPoint where pin in ('123', '456', '789);


I thought of changing it to a function, but its in use in many places in 
the code as:
select * from getPoint where pin = '12345';


So I've run out of ideas now.  Any hints or pointers on how I can get 
the limit to work inside the view?  Or some other way?

Thanks for your time,

-Andy

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