Re: Nested Sets vs. Nested Intervals

From: asdf <xyz91234_at_yahoo.com>
Date: 16 Nov 2005 15:48:41 -0800
Message-ID: <1132184921.633240.267030@f14g2000cwb.googlegroups.com>

Thank you very much!

You said the examples are fast, is there any significant speed difference to the nested intervals model? What's the speed difference between the multiple selects adjacency list example shown above and this:

SELECT t1.name AS lev1, t2.name as lev2, t3.name as lev3, t4.name as lev4 t5.name as lev5 t6.name as lev6
FROM web_directory AS t1

LEFT JOIN web_directory AS t2 ON t2.parent = t1.id
LEFT JOIN web_directory AS t3 ON t3.parent = t2.id
LEFT JOIN web_directory AS t4 ON t4.parent = t3.id
LEFT JOIN web_directory AS t5 ON t5.parent = t4.id
LEFT JOIN web_directory AS t6 ON t6.parent = t5.id

WHERE t1.name = 'Games'

AND t2.name = 'Board Games'
AND t3.name = 'Abstract';
AND t4.name = 'Chess';
AND t5.name = 'Software';
AND t6.name = 'Web Chess Viewers';

What speed advantages do the nested intervals model have that that adjacency list doesn't? Received on Wed Nov 16 2005 - 17:48:41 CST