Re: performance question

From: Niall Litchfield <niall.litchfield_at_dial.pipex.com>
Date: Fri, 11 Feb 2005 06:31:07 -0000
Message-ID: <420c5125$0$19165$cc9e4d1f@news-text.dial.pipex.com>

"Jan van Veldhuizen" <jan_at_van-veldhuizen.nl> wrote in message news:4209d2a5$0$28984$e4fe514c_at_news.xs4all.nl...
> Currently my first task is to get the application working for both
> databases
> by replacing the Sqlsrerver specific statements by generic SQL.

If you can restrict your customers to SQL Server 2000 or Oracle 9 and above (in Oracle's case that means all supported versions so it shouldn't be too onerous) then you may get a long way with writing your SQL using the newer select .... FROM tablea INNER JOIN table b ON (joins) .... syntax which both support.

In addition you should consider carefully the locking models of both databases (or transaction isolation levels if you prefer), because these are different your app *may* give different results for the same data and the same SQL statements (admittedly this is not likely, but it is possible).

-- 
Niall Litchfield
Oracle DBA
http://www.niall.litchfield.dial.pipex.com

Received on Fri Feb 11 2005 - 00:31:07 CST