Stefan Keller writes:
> There seems to exist some opportunities now with GIST which relate to
> geometry/geography types (but not only...):
> 1. Index-only scans on geometry columns with SP-GIST (being able to do
> a "SELECT id FROM my_table WHERE mygeom...;").
Well, if somebody builds an SP-GiST
Tom,
There seems to exist some opportunities now with GIST which relate to
geometry/geography types (but not only...):
1. Index-only scans on geometry columns with SP-GIST (being able to do
a "SELECT id FROM my_table WHERE mygeom...;").
2. Index clustering incuding NULL values (i.e. being able to d
Jesper Krogh writes:
> On 2011-12-14 19:48, Tom Lane wrote:
>> I think this is somewhat wishful thinking unfortunately. The difficulty
>> is that if the index isn't capable of reconstructing the original value,
>> then it's probably giving only an approximate (lossy) answer, which
>> means we'll
On 2011-12-14 19:48, Tom Lane wrote:
Jesper Krogh writes:
On 2011-12-14 19:00, Tom Lane wrote:
So the problem is that we have to either disallow such opclass designs,
or support per-opclass rather than per-index-AM decisions about whether
index-only scans are possible.
Just a quick comment, f
Jesper Krogh writes:
> On 2011-12-14 19:00, Tom Lane wrote:
>> So the problem is that we have to either disallow such opclass designs,
>> or support per-opclass rather than per-index-AM decisions about whether
>> index-only scans are possible.
> Just a quick comment, for some queries like the fam
On 2011-12-14 19:00, Tom Lane wrote:
So the problem is that we have to either disallow such opclass designs,
or support per-opclass rather than per-index-AM decisions about whether
index-only scans are possible.
Just a quick comment, for some queries like the famous
select count(*) from table w
It would not take very much at all to make the SP-GiST stuff support
index-only scans, except for one thing: it's conceivable that an opclass
might choose to store only a lossy version of the original indexed
datum, in which case it'd not be able to reconstruct the datum on
demand.
I'm not sure ho
