kvf77 дык не одинаковый!..
CREATE TABLE categories (
cid int(10) unsigned NOT NULL auto_increment,
title varchar(128) NOT NULL default '',
cleft int(10) unsigned NOT NULL default '0',
cright int(10) unsigned NOT NULL default '0',
clevel int(10) unsigned NOT NULL default '0',
PRIMARY KEY (cid),
KEY cleft (cleft, cright, clevel)
) TYPE=MyISAM;
и
CREATE TABLE tb_nodes (
STRID int(11) NOT NULL auto_increment,
ROOTID int(11) NOT NULL default '0',
l int(11) NOT NULL default '0',
r int(11) NOT NULL default '0',
PARENT int(11) NOT NULL default '0',
STREH int(11) NOT NULL default '0',
LEVEL int(11) NOT NULL default '0',
STRNA char(128) NOT NULL default '',
PRIMARY KEY (STRID),
KEY ROOTID (ROOTID),
KEY STREH (STREH),
KEY l (l),
KEY r (r),
KEY LEVEL (LEVEL),
KEY SRLR (ROOTID,l,r),
KEY parent (PARENT)
) TYPE=MyISAM COMMENT='NestedSet table';
Тут ещё и парент, и много "корней" может быть...