RE: dbimport feature/bug on 9.40HC3

John, Dbimport has only recently started calculating the extent sizes. It certainly didn't attempt to do it back in 1990. I know I worked for Informix in those days and was one of the people who discovered the need to set extent sizes after dbexport. After all dbexport -ss is a fairly recent innovation. And yes, there is no varchar in SE. But there is in Online 5, and IDS 7, and migration from them also needs to use dbexport/dbimport. Many of us in the real world are faced with customers who have been using Informix products for many years on these old - but still very reliable - platforms. They are often being forced to migrate to IDS 9 and even 10. The pressures on the migration are that the hardware is getting old and when they replace it they discover they can no longer get the old OS, and the old versions of Informix for the new OS. So they take their tried and trusted application and come to people like us looking for a solution. And we should be trying to help them not presenting them with "your 1 Gbyte database will now require 8Gbytes". Fortunately most of these systems migrate to much bigger hardware for much less price so the problem isn't always that grave. And the original problem I had was that the customer was migrating from 9.2 to 9.4. And yes they should have calculated the extent sizes properly for 9.2. And yes, they could have migrated in place. But there were many acceptable reasons why these things hadn't happened. The extent sizes had never been set as their previous Informix support people had never bothered to do it. They couldn't update in place as they wanted to migrate to a different operating system. And in my case the customer had looked at how much disk space the old system took and bought similar amounts. Fortunately we now have a resolution for that customer and for future migrations I have implemented a Database sizing phase in all conversion plans. I have quoted the original case number in this thread. I assume you have the tools to find it. And Sucwinder Bassi worked with me on it. Regards Malcolm -----Original Message----- From: John Dryburgh [mailto:dryburghj@yahoo.com] Sent: 30 April 2005 10:43 To: malcolm weallans Subject: Re: dbimport feature/bug on 9.40HC3 there is no varchar in standard engine. back in 1990, long before I worked for Informix, there were problems with dbexport and dbimport miscalculating the size of extents. i used to distribute a demo along with online 5 which included the complete works of sheakspeare and the dbimport wouldn't load without some tinkering because it miscalculated the extents. IBM make a best guess. I doubt they'll ever get it perfect. however if you did have a bug logged that you don't think has been fully fixed, do you have the bug number I'll have a look. --- malcolm weallans <malcolm.iiug@btopenworld.com> wrote: > And then I could argue that when migrating from > standard engine to IDS the -ss option is a little > bit > of a problem. > > Come off it John, we all know that the original > purpose of dbexport/dbimport was to migrate > databases > fom SE to IDS and we all know what a pig it is to > calculate extent sizes. We also know that if a > table > takes too many extents it will cause performance > problems, if not initially then eventually, and I'm > sure we all know that before the advent of detached > indexes this was not a problem. It is now. And if > IBM don't manage to do something about it they will antagonise > customers. > > If IBM need my help with how to do it I'm sure my > company will sell my services. > > regards > > Malcolm > > > --- scottishpoet <dryburghj@yahoo.com> wrote: > > And I suppose IBM could argue a better procedure > > could be to dbexport > > with the -ss option > > > > > Send instant messages to your online friends http://uk.messenger.yahoo.com sending to informix-list