Re: new module contrib/tree for 7.2 ? - Mailing list pgsql-hackers

On Fri, 22 Feb 2002, Bruce Momjian wrote:

>
> Oleg, can you send over a patch?
>

As soon as I write documentation :-) I hope I could use this weekend
Oleg

> ---------------------------------------------------------------------------
>
> Oleg Bartunov wrote:
> > Hi,
> >
> > Is't late to submit new contrib module for 7.2 ?
> > It's almost ready and tested, we have to write README.tree.
> >
> > New module creates new data types 'tree', 'treequery' for tree-like data and
> > provides indexed access methods using Btree or GiST.
> > Node represents as a path to the root, so record like '3.4' means
> > 4-th child of 3-rd child of the root node.
> > Due-to bit-representation there is a limitation to the number of
> > children - 64 and defined in compile time (valid values - 8,16,32,64).
> > For practical purposes 64 children looks quite enough.
> > insert,delete operations should be ok, while move operations
> > is a pain - one should update all paths of children nodes.
> > But search is very fast, we use data from Open Directory catalog (www.dmoz.org)
> > for testing:
> >
> > Select all countries:
> >
> > dmoz64=# explain analyze select * from dmoz where tid <* '18.*.0';
> > NOTICE:  QUERY PLAN:
> >
> > Index Scan using tid_g_idx on dmoz  (cost=0.00..1094.10 rows=277 width=100) (actual time=3.54..23.76 rows=56
loops=1)
> > Total runtime: 23.96 msec
> >
> > EXPLAIN
> > dmoz64=#
> >
> >        name         |             strid             |   id   |  tid
> > ---------------------+-------------------------------+--------+-------
> >  Tagalog             | Top/World/Tagalog             | 276537 | 18.18
> >  Taiwanese           | Top/World/Taiwanese           | 276566 | 18.19
> >  Tamil               | Top/World/Tamil               | 276567 | 18.20
> >  Telugu              | Top/World/Telugu              | 276568 | 18.21
> >  Thai                | Top/World/Thai                | 276601 | 18.22
> >  Ukrainian           | Top/World/Ukrainian           | 276602 | 18.23
> >  Vietnamese          | Top/World/Vietnamese          | 276603 | 18.24
> >  Japanese            | Top/World/Japanese            | 268629 | 18.31
> >  Kiswahili           | Top/World/Kiswahili           | 268630 | 18.32
> >  Afrikaans           | Top/World/Afrikaans           | 256813 | 18.1
> >  Italiano            | Top/World/Italiano            | 266163 | 18.30
> >  Interlingua         | Top/World/Interlingua         | 266144 | 18.29
> >  Indonesia           | Top/World/Indonesia           | 265859 | 18.28
> >  Croatian            | Top/World/Croatian            | 257063 | 18.12
> > ....................................................................
> >
> >
> >
> >     Regards,
> >         Oleg
> > _____________________________________________________________
> > Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
> > Sternberg Astronomical Institute, Moscow University (Russia)
> > Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
> > phone: +007(095)939-16-83, +007(095)939-23-83
> >
> >
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> >
> > http://www.postgresql.org/users-lounge/docs/faq.html
> >
>
>
Regards,    Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83