[...]
> Well, not exactly: it's significant faster on SQL Server *and* Oracle.

That's a hard statement ;) Did you (or someone else) try to find out the reason 
for this? MaxDB comes by standard installation with a configuration, that is 
suitable for "usual R/3 OTLP" configurations, this may not be the right one for 
your environment. If the differences are that significant, I'm sure it would be 
of interest, why it behaves like this.

[...]
> True, but there are scenarios where you do not want to lump everything
> in one single SAN because you want to reserve part of the IO bandwidth
> for particular tasks (parts of the schema).  Or you want to be able to
> take individual tablespaces offline and manipulate them independently.

We have actually two SAN systems but we put the production OLTP, the production 
BW and production CRM on one box - and still don't reach the cricitical I/O 
bandwidth where one system slows down the other, even during usual working days 
where all three systems run on their usual load we don't reach that point (yet).

> I understand the reasoning behind MaxDB's approach to distribute data
> evenly across volumes but this only works good if you have them on
> physically separate disks.  Even in that case you might suffer major
> data loss if one volume is corrupt.  I may be missing something but I
> am not aware of a way to extend a volume if you need more space. And
> that seems a fairly common thing to do - especially with SAN's which
> can grow seamlessly. Then again you might say that multiple volumes on
> a single SAN are not a performance issue because there is no
> hotspot...

You can't "grow" a volume but you can add another one; the system tries then to 
evenly distribute the data again across all volumes. In low I/O times, the DB 
also moves the blocks to the new volume so you will end finally with database 
of even distributed data across all volumes. This is true for usual OLTP 
databases, for OLAP this concept has changed with the implementation for the BI 
feature pack (as far as I technically understood the details).

[...]
> The difference here is that you do not have to migrate from 8 to 10 as
> often as you have to migrate from MaxDB 7.5 to newer versions.

You usually migrate once from 7.5 to 7.6 ;) 

I think, that one of the main reasons, why companies decided to use Oracle is: 
Oracle is well known, widely accepted and the de-facto standard database. If 
someone chooses a different database, the (I call it) ATV (accepted tolerance 
value), is MUCH lower with other databases, although many problems, whatever 
kind, could certainly be solved with an appropriate amount of time. If you have 
a problem with MaxDB, everyone would say "If we were staying with Oracle...". 
If Oracle has a big problem in whatever area, you just live with it - because 
it's Oracle. You take into account and install dozens of patches on your 
systems, hire additional DBAs just because it's like it is, and it's accepted 
like this.

I'm sure that, if you would invest the same amount of time initially for a 
MaxDB migration as you needed to get your Oracle databases installed, patched 
and tuned, you would get almost similar results. 

Your points are really interesting, it's not about a flame war here but 
interesting, why one chose to not use MaxDB. 


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