You may want to check out using Nested Sets instead of a Parent-Child-ID system. I think it's an easier system for representing hierarchies. Here is a good article on the system: http://searchdatabase.techtarget.com/tip/1,289483,sid13_gci537290,00.html Google for Nested Sets +sql or something and there are more articles out there. It's sort of confusing in the beginning. If you have any questions, let's take it off the PHP list. ---John Holmes... ----- Original Message ----- From: "David Elliott" <david@elliott.uk.com> To: "Adam Voigt on PHP-DB" <php-db@lists.php.net> Sent: Tuesday, November 26, 2002 9:41 AM Subject: Re: MySQL/PHP Iterative Tree > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Hello Adam > > On 26 November 2002 at 08:25:22 -0500 (which was 13:25 where I live) Adam > Voigt emanated these words of wisdom > > < ... > > > > Ok, and I am using this structure to make a kind of drill down > > structure, so the top level would be where parentid = '0', then > > you take those id's and select from this table where parentid is > > equal to those id's, and now your starting to navigate through > > the tree, and so on. > > > Now, the real question, I have found a Javascript menu script which > > will let users of the site click on it, and then click on the submenu > > and down and down through all the level's that might dynamically exist, > > Be careful of the size and the time it takes to build a big tree. > > > but I can't for the life of me figure out how to recursively get the > > name and id for each row (which is what I need to build the menu and > > make link's out of each item), for as many sublevel's as there might be > > (infinite). Am I missing something, is there a simple logical way to do > > this recursively? Or if there's a semi-complex way, anyone got a script > > example? I'd very much appreciate it. > > This is not much help but have done something like that in MSSQL with stored > procedure (about 120 to 150 lines of SQL). > > The logic went something like. > > get all top level > put into a temptable_1 > go through temptable_1 > put line into temptable_2 noting level > add on any children for line into temptable_2 > next line of temptable_1 > copy temptable_2 to temptable_1 > keep going through temptable_1 until there is no more children at last level > > I also used a separate table for the links this way it is easier to go both > up and down the tree. > > What would be nice is to do it dynamically and display only the tree that > you need and just get the data for the children when needed. eg like MSDSon > M$ site > > - -- > TTFN, _______________________________________________ > David | David Elliott | Software Engineer | > _________________________| david@elliott.uk.com | PGP Key ID 0x650F4534 | > | I am Barney of Borg...Sesame Street will be assimilated. | > > -----BEGIN PGP SIGNATURE----- > Version: 6.5.8ckt http://www.ipgpp.com/ > > iQA/AwUBPeOIC/mK8eZlD0U0EQI8YQCdEKtpYBkVNmLGYEs2xt3RKBoh1A0An2FG > KzmAxhrABe/7JZxw3mvmYkaJ > =xdTm > -----END PGP SIGNATURE----- > > > -- > PHP Database Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
