Re: VARCHAR2 storage on a page

"Niall Litchfield" <n-litchfield_at_audit-commission.gov.uk> wrote in message news:3cd8e597$0$236$ed9e5944_at_reading.news.pipex.net...
>
> I can't speak for Informix but the example I use when talking about
porting
> code between platforms consists of porting the following Oracle code
to
> MSSQL.
Recall that the original poster stated that they are a DBA, they weren't porting code. So I'd like to know what assumptions an Informix DBA might make which would cause the dire warnings that were posted.

> update emp set sal = sal * 1.05;
> insert into emp_audit(change_date,change_desc) values
(sysdate,'Annual
> Salary increase all staff 5%');
> commit;
>
> which is fairly self explanatory.
>
> In MSSQL if , for example, the insert fails then the update will be
made
> without having being logged.

What do you mean without being logged? As in the actual transaction log? (which I don't believe you mean).

> I don't think that it is unreasonable to assume that the above will
be
> processed the same in different databases, but it won't be.

Possibly but I think some projecting is happening here ... <g>

> In addition I would guess that the OP is making the correct, but
misleading
> assumption that Oracle like Informix has a fixed page/block size.
The Oracle
> block size is only fixed at database creation it is not dictated by
the
> underlying platform. (and in 9i you can subsequently create
tablespaces with
> different block sizes from the database block size).

I understand the above but fail to see how it dovetails into the dire warnings presented. It's not going to cause corruption etc.

Thx!

--
Pablo Sanchez, High-Performance Database Engineering
mailto:pablo_at_hpdbe.com
http://www.hpdbe.com
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