Well, not easy in a programming language - however, certainly an option. I
was hoping that there would be some kind of break in sequence aggregation
available (or a trick) in Sqlite. My problem I suspect is not so uncommon. I
know that I can do this in INFO (an outdated database of ArcInfo) and I
On 8/16/2011 4:58 PM, Anantha Prasad wrote:
> The data is sorted by Longitude and then by Distance. Whenever there are
> repeated values of Distance within a Longitude, I want the Sum and Count to
> be added and divided
select Longitude, Distance, sum(SumColz) / sum(CountColz) as AvgColz
from my_t
On 16 Aug 2011, at 9:58pm, Anantha Prasad wrote:
> The data is sorted by Longitude and then by Distance. Whenever there are
> repeated values of Distance within a Longitude, I want the Sum and Count to
> be added and divided - for example,
> Here is the table:
> Longitude Distance AvgColz SumCo
Thanks much for the responses - they were helpful but was not quite what i
wanted. Perhaps I was not clear. So, here goes...
The data is sorted by Longitude and then by Distance. Whenever there are
repeated values of Distance within a Longitude, I want the Sum and Count to
be added and divided - f
I think it will have better performance if you do that in your
programming language. But if you insist on SQL it would look like
this:
update table_name set IVmean =
(select sum(IVsum)/sum(IVcount) from table_name t
where t.Longitude = table_name.Longitude
and t.Distance = table_name.Distance);
I
You can't replace multiple rows in a single insert/update/delete statement.
You might consider copying the duplicates to a temp table, delete them
from the old then use a select on the temp table to generate the new
rows for the old table. The select portion would be something like
select longit
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