Re: Oracle 11 Server and Unicode UTF-8

From: Frank van Bortel <>
Date: Sat, 29 May 2010 11:57:49 +0200
Message-ID: <9480f$4c00e51d$524ba3af$>

On 05/27/2010 08:49 PM, Walt wrote:
> Hi,
> We're running Oracle 10g on Windows using ISO 8859 as the character set.
> We're exploring the idea of converting to unicode (UTF8) along with the
> upcoming upgrade to v11.
> I haven't found a good reference for how to best accomplish the
> conversion and what pitfalls to watch out for. Any suggestions?
> One thing I expect to be a problem is that we have about 200 columns
> that are defined as Varchar2(4000). My understanding is that this limit
> is 4000 *bytes* so some of our data may not "fit" if it contains enough
> characters with ascii values above 128.
> Anyone been through this before who'd like to offer sage advice?
> Thanks.
> //Walt

Why would you switch to Unicode? Why not to WE8MSWIN1252? anything MS Windows can throw at you is supported. And databases generally store whatever you feed them (code points! Not characters). See

Apart from the obvious length problems, there are the bugs introduces by the fact you use a variable length character set. If any, I'd go for a fixed length set, like AL16UTF16 (which also better aligns with Java, and MS Windows - the latter using UCS2, which is regarded a forerunner of UTF16)



Frank van Bortel
Received on Sat May 29 2010 - 04:57:49 CDT

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