Reiner Dassing <[EMAIL PROTECTED]> writes:
> Here is another example, which is even worse:
> select value from table where id=1 order by epoch desc limit 1;
> to ask for the last stored value.
> This request needs about 5 minutes to complete.
Hm. That should produce a decent plan given the right
Bruce Momjian wrote:
>
> The larger problem is that count(*) doesn't use the index at all. It
> just does a sequential scan of the heap table.
Here is another example, which is even worse:
select value from table where id=1 order by epoch desc limit 1;
to ask for the last stored value.
This re
> > I assume the user is concerned about non-balanced btrees.
> That is correct!
> As I tested an example database with about 7 million entries on PostgreSQL V
> 6.5.2
> and the result of
> select count(*) from table;
> tooks about 3 minutes I have this concern.
> May be version 7.0.3 will give
Bruce Momjian wrote:
>
> > Reiner Dassing <[EMAIL PROTECTED]> writes:
> > > The primary index must be the epoch.
> > > As there will be no deletion from this data I fear - due to the
> > > internal representation of B-trees - the performance will degrade very
> > > soon.
> >
> > Nonsense. btree
> Reiner Dassing <[EMAIL PROTECTED]> writes:
> > The primary index must be the epoch.
> > As there will be no deletion from this data I fear - due to the
> > internal representation of B-trees - the performance will degrade very
> > soon.
>
> Nonsense. btree should work just fine for that. Use
Reiner Dassing <[EMAIL PROTECTED]> writes:
> The primary index must be the epoch.
> As there will be no deletion from this data I fear - due to the
> internal representation of B-trees - the performance will degrade very
> soon.
Nonsense. btree should work just fine for that. Use a timestamp
co
Hi!
I am thinking about the best structure of a database to describe timely ordered
values.
The timely ordered values are the results of different sensors measuring
environmental
parameters like temperatur, pressure, humidity.
The database has to define the kind of measurements, kind of sensors,
