Hi Mike, It sounds like what you need to know is what a B-tree index is and how it works. I took a course in Data Structures and Algorithms that taught it to me. Try
http://www.bluerwhite.org/btree/ and the links at the bottom. Specifically, "B-Tree-Delete Deletion of a key from a b-tree is possible; however, special care must be taken to ensure that the properties of a b-tree are maintained. Several cases must be considered. If the deletion reduces the number of keys in a node below the minimum degree of the tree, this violation must be corrected by combining several nodes and possibly reducing the height of the tree. If the key has children, the children must be rearranged." So it depends what the B-tree index in MySQL uses as the minimum degree of the tree. I wish I had 1/2 an hour or an hour to sit down and explain how a B-tree works, but I think the link above explains it pretty well. -Sheeri On 11/23/05, Mike OK <[EMAIL PROTECTED]> wrote: > Thanks for the point to the internals. I will keep this page bookmarked. I > read everything there regarding indexes and did not find the answer I was > looking for. I think what I need falls under the UPDATE statement (no > listing there). Specifically, what triggers the action for index re-builds. > Is it the "row changed" flag or is there a "column changed" flag ??? Mike > > > ----- Original Message ----- > From: "Gleb Paharenko" <[EMAIL PROTECTED]> > To: <mysql@lists.mysql.com> > Sent: November 23, 2005 5:51 AM > Subject: Re: UPDATE and INDEX updates > > > > Hello. > > > > > don't think I will find the answer to this question in the normal > >manuals > > > but rather from someone / place that deals with the internals of the > > >system. > > > Mike > > > > MySQL internals are available at: > > http://dev.mysql.com/doc/internals/en/ > > > > > > > > Mike OK wrote: > > > I did read the manuals (three including MySQL reference manual and > DuBois > > > ver 5) as well as Google searches. I am using Myisam tables (installed > by > > > default) and from what I can tell by the from the manual the indexes > would > > > be B-tree but I would be willing to work with another type if necessary. > I > > > don't think I will find the answer to this question in the normal > manuals > > > but rather from someone / place that deals with the internals of the > system. > > > Mike > > > > > > > > > > > > -- > > For technical support contracts, goto https://order.mysql.com/?ref=ensita > > This email is sponsored by Ensita.NET http://www.ensita.net/ > > __ ___ ___ ____ __ > > / |/ /_ __/ __/ __ \/ / Gleb Paharenko > > / /|_/ / // /\ \/ /_/ / /__ [EMAIL PROTECTED] > > /_/ /_/\_, /___/\___\_\___/ MySQL AB / Ensita.NET > > <___/ www.mysql.com > > > > > > > > > > -- > > MySQL General Mailing List > > For list archives: http://lists.mysql.com/mysql > > To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] > > > > > > > > -- > > No virus found in this incoming message. > > Checked by AVG Free Edition. > > Version: 7.1.362 / Virus Database: 267.13.5/177 - Release Date: 2005-11-21 > > > > > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] > > -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
