On 26.02.2015 13:37, Heikki Linnakangas wrote:
On 02/26/2015 12:31 AM, Josh Berkus wrote:
On 02/14/2015 10:35 AM, Sven R. Kunze wrote:
Thanks for the immediate reply.
I understand the use case is quite limited.
On the other hand, I see potential when it comes to applications which
use PostgreSQL. There, programmers would have to change a lot of
code to
tweak existing (and more importantly working) queries to
hash/reverse an
id column first. Using ORMs would make this change even more painful
and
maybe even impossible.
When reading
https://richardfoote.wordpress.com/2008/01/14/introduction-to-reverse-key-indexes-part-i/
carefully, it also seems to work with index scan partially in case of
equality comparisons.
Seems like a good use for SP-GiST. Go for it!
A b-tree opclass that just compares from right-to-left would work just
as well, and perform better.
- Heikki
Thanks for the hint. That also sounds easy to implement.
Regards,
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Sven R. Kunze
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