I know this is an old topic, but it's not easy to find a way around it, so
when we migrate SQL from other database to PostgreSQL, it causes a huge
headache. Here's an extremely simple example -
The original simple SQL -
select distinct atcode from TMP order by torder;
(it'll error out in PostgreSQL, although SQL92 extension may allow it;
there's time you just can't do "select distinct atcode,torder from TMP order
by torder"!!)
My desire result -
HGB
HCT
WBC
RBC
MCV
MCH
MCHC
RDW
RDWSD
PLT
DIFF | TYPE
SEGS
LYMPHS
MONOS
EOS
BASOS
I tried to rewrite the above simple query in PostgreSQL as - select distinct
atcode from (select atcode,torder from TMP order by torder) t;
But the return results are not what I want - BASOS DIFF | TYPE EOS HCT
HGB LYMPHS MCH MCHC MCV MONOS PLT RBC RDW RDWSD SEGS WBC
Can anybody provide a real/general solution to the above practical problem?
(Tom?) This causes postgreSQL users too much time and headache.
Thanks.
johnl
---------------------------(end of broadcast)---------------------------
TIP 6: Have you searched our list archives?
http://archives.postgresql.org
