union in subselect?

Hi all,

Can you use (or work around towards) a union in a subquery?

I have :-

Members
mid int4;
mnec bool; -- many NEC members

Positions (one position = one holder - excludes NEC)
posn char(4);
pholder int4; -- refers to mid

Actions
caction char(4) -- e.g. UPDT = update team
cposn char(4) -- refers to posn
clevle int4 -- increasing permission level

select 'NEC' as posn from members where mid = 81 and mnec = true;
posn
------
NEC
(1 row)

select posn from positions where pholder = 81;
posn
------
MSEC
ITA
REG
(3 rows)

select posn from positions where pholder = 81 union select 'NEC' as posn from
members where mnec = true and mid = 81;
posn
------
ITA
MSEC
NEC
REG
(4 rows)

So far so good.
select * from actions where cposn in (select posn from positions where
pholder = 81);
caction | cposn | clevel
---------+-------+--------
ENQT | REG | 2
ENQM | REG | 2
AMET | REG | 2
AMET | ITA | 3

Still works - looking good

select * from actions where cposn in (select posn from positions where pholder
= 81 union select 'NEC' as posn from members where mnec = true and mid = 81);

gives me:

ERROR: parser: parse error at or near "union"

--
Gary Stainburn

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