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RE: Which Character Set for 9.2

From: Janardhana Babu Donga <>
Date: Fri, 29 Oct 2004 09:06:23 -0700
Message-ID: <>

Dear List,  

I am of the opinion that Oracle uses 8bits to store the data, but just most significant bit is not used, and so the data in US7ASCII character set is OK and not corrupted. Am I correct ?  

If it is really going to be a lot of corruption because of 7-bits, I may better convert the database character set from US7ASCII to WE8ISO8859P1 asap. Any Comments?  

From: M.Godlewski [] Sent: Friday, October 29, 2004 6:35 AM
Subject: RE: Which Character Set for 9.2  


I think people are changing character sets to avoid the possibility of corruption.  

If the client your using has a different character set i.e. WE8ISO8859P1 and your database has a character set of US7ASCII, then when you store data in the database it requires 8 bits to store it, and there are only 7 bits available in the database. You will find your data has the potential for corruption. You will see question marks returned when you go to pull the data out of the database.  

If your database has 8 bits available to store the 8 bits of client data, then when you retrieve the data you will see the data without question marks.  

There are some articles on metalink about sub sets and super sets of the character set. You may want to have a look.

Janardhana Babu Donga <> wrote:

Why is the 8 bits good and 7 bits bad?
Is there any valid reason?

-----Original Message-----
From: Niall Litchfield [] Sent: Wednesday, October 27, 2004 1:58 PM To:
Cc: Nelson, Allan;;;
Subject: Re: Which Character Set for 9.2

On Wed, 27 Oct 2004 10:05:34 -0700, Janardhana Babu Donga wrote:
> Dear List,
> If it is not required to convert from US7ASCII to WE8ISO8859P1, I don't
> understand why so many people are changing their character set to
> WE8ISO8859P1 from US7ASCII. Could some one explain please?

7bits bad, 8 bits good.

Niall Litchfield
Oracle DBA


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Received on Fri Oct 29 2004 - 11:02:11 CDT

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