I'm not about to argue one database over another. I've worked a lot in databases that don't enforce integrity, and you need to include the integrity in your code. This is sometimes easier said than done. We began using Postgres at the very start of Koha, but found problems making some queries run efficiently. MySQL ran them so we changed. I don't know to what extent the problem were in my lack of experience and how much was the fault of Postgres, and how much the two database have changed in the meantime. -----Original Message----- From: Larry Currie [mailto:lcurrie@CalAcademy.Org] Sent: Thursday, January 16, 2003 1:38 PM To: koha@lists.katipo.co.nz Subject: [Koha] MySQL and foreign keys Last night I attended a PerlMongers group meeting here in Oakland, CA and one of the presenters at the meeting asserted that MySQL could not claim to be a completely relational database because it doesn't let you define foreign keys. As a result, he feels that MySQL fails the ACID test (atomicity, consistency, referential integrity, and durability), and he advised people to avoid using it in Perl applications and instead use Postgres or some other relational database with more stability. He cited an example where you might have a one-to-one relationship between primary key values in two tables and if you deleted a value from one of the tables, MySQL would leave that value in the other table as dangling data without warning you to take care of it and as a result really mess up your database. Can anyone on the Koha list comment on this assertion and what the consequences might be for Koha? ____________________________________________________________________ CAUTION - This message may contain privileged and confidential information intended only for the use of the addressee named above. If you are not the intended recipient of this message you are hereby notified that any use, dissemination, distribution or reproduction of this message is prohibited. If you have received this message in error please notify Safe Air Ltd immediately. Any views expressed in this message are those of the individual sender and may not necessarily reflect the views of Safe Air. _____________________________________________________________________ For more information on the Safe Air Group, visit us online at http://www.safeair.co.nz/ _____________________________________________________________________