Brent Wood wrote:
That gets back to how nulls should be handled generally.
If you take the sum() (or avg(), max(), etc) of a numeric column with nulls, 
what should the result be?

In postgresql, nulls are ignored. To see this, run this query:

select sum(numbers.value), avg(numbers.value), max(numbers.value)
from
(select 1 as value
union
select null as value) as numbers

The results are:

sum  avg                     max
  1  1.00000000000000000000   1

Is an empty geometry value different from a null in a geometry column?

I'll leave that to other to decide - but I don't see why a null geometry is tied to a SRID.

Can an empty geometry have a SRID (& a null can't)?

A null geometry does have an SRID which is the root of the problem.

Charlie

Attachment: smime.p7s
Description: S/MIME Cryptographic Signature

_______________________________________________
postgis-users mailing list
[email protected]
http://postgis.refractions.net/mailman/listinfo/postgis-users

Reply via email to