O Oleg Bartunov έγραψε στις Nov 17, 2004 :
> Gary,
>
> if you need really fast solution for you task and dont't afraid
> non-standard soltion, take a look on contrib/ltree module.
> http://www.sai.msu.su/~megera/postgres/gist/ltree/
>
> Oleg
Oleg how would you compare an ltree solution against a
genealogical approach using intarray??
i.e. store for each node, its path to root,
e.g. path='{4,2,7}'::int4[] where 4 is the id of the father,
2 of the grandfather, and 7 of the root, whereas root has
path is null.
That way we can do really fast queries using ~, have indexes
on level (path length),first (immediate ancestor),last (root)
using C functions that we can easily write and so forth.
I have extensively used this approach with success.
Can you comment on the pros and cons of each? (int[] with intarray vs
ltree).
Thanx
> _____________________________________________________________
> 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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