Re: Data Structure for use vs storage

"Dmitry Ivanov (as ystok-systema at mail dot ru)" <[email protected]>
Newsgroups gmane.lisp.lispworks.general
Organization Исток-Системы
Message-ID <op.3kxijjs2ux7y3r@gigo>
David McClain (as dbm at refined-audiometrics dot com) wrote:

> I looked at the BTree code. Interesting. But when would you use this  
> over the built-in Hashtables of Common Lisp? In fact, with Hashtables,  
> you don’t even need an ordering to the underlying data, just an equality  
> comparison.

In addition to a hashtable, you can maintain a BTree index on a "primary  
key" column. That would considerably speed up queries like this:

(bplustree-search-range 501 1000 *my-tree*)

-- 
Dmitry Ivanov
lisp.ystok.ru

_______________________________________________
Lisp Hug - the mailing list for LispWorks users
[email protected]
http://www.lispworks.com/support/lisp-hug.html
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.