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Hi,
My postings seem to double on me. Well thanks
to everybody that answered. They were not the answers I was hoping for
but, I found one in the docs. Let me explain again what I'm doing with a
example:
table:
points id
distance
1
25 0.26598333
1
32 0.65983600
1
56 1.23692000
2
96 120.26659366
2
32 0.54865130
etc
Now select for point 1 where id = min(distance).
The trick I was suspecting but not been able to grasp is the use of aliases. In
Bruce Momjian's "Postgresql: introduction and limitations" was an example like
this with structure from the problem here:
select p.points, p.id, p.distance
from table as p
where distance = (select min(distance)
from table as p1
where p.points=p1points)
order by points, id
Now this works. So going to the next question, if
distance is a calculated field how can I use it in the subquery.
How do you add another alias in:
select p.points, p.id, (x-x) as distance
from table as p
where distance = (select min(distance)
from table as p1
where p.points=p1points)
order by points, id This of course doesn't work, because of the
referring to the calculated field wich is not actually a part of the
table. Can you do this somehow or is it impossible?
Love to hear from you guys,
greetz Sjors
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- Re: [SQL] howto/min values Sjors
- Re: [SQL] howto/min values Christoph Haller
