That's not the way I've got my db set up. Mine looks like this: id|name|parent 1|Books|0 2|Sci/Fi|1 3|Starship Troopers|2 4|Friday|2
So if I deleted Sci/Fi, records 3 and 4 would be orphaned. I'm using mySQL by the way (if it matters). <!----------------//------ andy matthews web developer ICGLink, Inc. [EMAIL PROTECTED] 615.370.1530 x737 --------------//---------> -----Original Message----- From: Barney Boisvert [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 31, 2006 5:31 PM To: CF-Talk Subject: Re: Nested Set Model Really, there's nothing to change. No triggers, procs, magic, or anything. Delete a record, and nothing in the tree gets orphaned. Say you've got a table like this: Name Left Right food 1 8 fruit 2 7 apple 3 4 banana 5 6 That is, food has a child fruit, which has two children apple and banana. Now delete fruit. Apple and banana are still inside the food set, without changing anything. Say you have the same tree, but with an adjacency list: name parent food NULL fruit food apple fruit banana fruit Now if you delete fruit, apple and banana are suddenly parentless, and they have no connection to food at all. Or they might have been inadvertantly deleted as well, if you've got a FOREIGN KEY with CASCADE DELETE set on the parent field. cheers, barneyb ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Message: http://www.houseoffusion.com/lists.cfm/link=i:4:230937 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
