even/odd is a little limiting, what happens down the road when another site needs to be added. A better method might be to use a unique session ID for each client site in combination with a generated sequence ID see the white paper at:http://www.ambysoft.com/persistenceLayer.html in particular the persistenceLayer.pdf document on that page.
Duncan Maitland wrote: >My questions concern a setup where a public server is running at our >hosting company and a local office server is behind a firewall >(connected to the net via a somewhat unreliable ADSL). > >The servers are configured in a circular master-slave relationship but >only a limited number of tables in the database are replicated between >the two (public doesn't need all of them, so no use in replicating). Of >these tables only 3 need to accept writes from both the public and >office server (all the other writes happen at the office). Of those 3 >tables only 1 makes use of a unique primary key. > > >So my questions are: > >1) Replicating a table with a primary key raises the possibility of >conflicts if, while the office link is broken, two records are created >with the same key. So I plan to generate my own keys in the project >source code (without auto_increment) - the public site generates records >with even numbers, the office site with odd numbers. > >Is this a reasonable setup or is there a more correct way? Out of >interest, how will MySQL 4.0 replication handle this situation? > > >2) MySQL docs state "It is possible for client A to make an update to >co-master 1, and in the meantime, before it propagates to co-master 2, >client B could make an update to co-master 2 that will make the update >of client A work differently than it did on co-master 1. Thus when the >update of client A will make it to co-master 2, it will produce tables >that will be different than what you have on co-master 1, even after all >the updates from co-master 2 have also propagated." > >Say the office link is down, and a particular record in the >above-mentioned table is edited on both the public and office servers. >When the servers re-sync will one record take precedence (if so, which >one?) or does the public get one and the office get the other? The >former seems to be the case when doing basic testing on my LAN at home, >but the MySQL doc is confusing in that it implies the latter. > > > >To those of you who have read all the way down to here, I thank you very >much! :) > >Cheers, >from Duncan Maitland >[EMAIL PROTECTED] > > >--------------------------------------------------------------------- >Before posting, please check: > http://www.mysql.com/manual.php (the manual) > http://lists.mysql.com/ (the list archive) > >To request this thread, e-mail <[EMAIL PROTECTED]> >To unsubscribe, e-mail <[EMAIL PROTECTED]> >Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php > > > -- Regards, Brent interactivetools.com, inc. Tel: (604)689-3347 - Fax: (604)689-3342 - Toll Free: 1(800)752-0455 Software for your Website - http://www.interactivetools.com/ Attachments accepted: TXT, HTML, RTF, PDF I do not accept attachments which are capable of harbouring viruses, for example Word for Windows. Please use File/Save As RTF or HTML. --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
