Re: Nested Coalescing possible in SQL?

"Lennart Jonsson" <lennart_at_kommunicera.umea.se> wrote in message news:6dae7e65.0406032300.77888608_at_posting.google.com...
> jlanfield2003_at_yahoo.com (Jeff Lanfield) wrote in message
news:<235c483f.0406031837.62f2701_at_posting.google.com>...
> Since youre mainly concerned in retrieving ancestors, (not
> investigating subtree
> ), I think it is a bit clumsy. Assume that you have a node x with path
> 1.2.3.56.89.112 and want to investigate which nodes in the path that
> have property p. How would you do that? Subtree queries are much
> easier since you can query: where path like '1.2.4.6.%'

Small procedural part -- table function -- which returns ancestors materialized path encodings set

1.2.3.56.89
1.2.3.56
1.2.3
1.2

for the input encoding 1.2.3.56.89.112 could be plugged in into the query returning all the ancestors. This idea translated into the nested intervals encoding (if you prefer to work with numbers instead of string parsing) is implemented at the end of

http://arxiv.org/html/cs.DB/0401014

BTW, http://arxiv.org/abs/cs.DB/0402051 is significantly rewritten. Essentially, it is Euclidean algorithm (the mother of all algorithms?) that is employed in the numerical counterpart of the Materialized Path. Received on Fri Jun 04 2004 - 19:47:30 CEST