Hi,
we've almost totally rewrite gist.c because old code and algorithm
were not suitable for variable size keys. I think it might be
submitted into 7.1 beta source tree. We have fixed several bugs and
memory leaks. Version for 7.0.3 is also available.
Sampe application for contrib area - implementation RD-Tree and index support
for int arrays I'll submit later (Need some documentation).
Regards,
Oleg
Here is a README.gist
--------------------------------
New version of gist.c for PostgreSQL 7.1
New feature:
1. Support of variable size keys - new algorithm of insertion to tree
(GLI - gist layrered insertion). Previous algorithm was implemented
as described in paper by Joseph M. Hellerstein et.al
"Generalized Search Trees for Database Systems". This (old)
algorithm was not suitable for variable size keys and could be
not effective ( walking up-down ) in case of multiple levels split
Bug fixed:
1. fixed bug in gistPageAddItem - key values were written to disk
uncompressed. This caused failure if decompression function
does real job.
2. NULLs handling - we keep NULLs in tree. Right way is to remove them,
but we don't know how to inform vacuum about index statistics. This is
just cosmetic warning message (like in case with R-Tree),
but I'm not sure how to recognize real problem if we remove NULLs
and suppress this warning as Tom suggested.
3. various memory leaks
All our tests and Gene Selcov's regression tests passed ok.
We have version also for 7.0.3
Sample application which utilize RD-Tree for index support of
int arrays is in contrib/intarray (will be submitted separately).
TODO:
1. Description of GLI algorithm
2. regression test for GiST (based on RD-Tree)
This work was done by Teodor Sigaev ([EMAIL PROTECTED]) and
Oleg Bartunov ([EMAIL PROTECTED]).
On Sun, 17 Dec 2000, Tom Lane wrote:
> Oleg Bartunov <[EMAIL PROTECTED]> writes:
> > I checked 7.1 feature list and didn't find any mention about GiST
> > but there are changes in GiST code. Who is a maintainer of GiST code ?
>
> You are ;-). If you expect to find someone who understands GiST better
> than you, you're probably out of luck.
>
> I recall having made a number of changes that applied to all of the
> index access methods, including GiST --- but I was just changing
> similar code in all the methods. I don't claim to know anything
> about GiST in particular.
>
> regards, tom lane
>
Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: [EMAIL PROTECTED], http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83
gist-7.1.tar.gz
