A. Kretschmer wrote:
In response to Tom :
I have a big table that is used for datalogging. I'm designing
graphing interface that will visualise the data. When the user is
looking at a small daterange I want the database to be queried for all
records, but when the user is 'zoomed out', looking at an overview, I
want run a query that skips every nth record and returns a managable
dataset that still gives a correct overview of the data without
slowing the programme down. Is there an easy way to do this that I
have overlooked? I looked at:
Do you have 8.4? If yes:
test=# create table data as select s as s from generate_Series(1,1000) s;
SELECT
test=*# select s from (select *, row_number() over (order by s) from
data) foo where row_number % 3 = 0 limit 10;
Won't this still read in the entire table and only then filter the
records out?
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