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From Satheesh Bandaram <sathe...@Sourcery.Org>
Subject Re: DB2 mode vs. Cloudscape mode
Date Fri, 04 Mar 2005 00:39:11 GMT
Yes, Cloudscape used to allow creating UNIQUE indexes on null columns,
but in a non-standard way. Old cloudscape used to allow only one NULL
value in the UNIQUE index, where as, I think the standard required
multiple NULL values.

I think making Derby handle multiple NULLs in UNIQUE index needs changes
to store/indexing.


Jeremy Boynes wrote:

> Satheesh Bandaram wrote:
>> Yes, you are right... The references to "DB2 mode" is from the past,
>> leftover comments. There is no distinction between the two.
> Did Cloudscape support UNIQUE on possibly null columns? If so, is this
> a restriction that we can easily remove or is there something deep in
> the index code that would make this problematic?
> Also, can anyone think of an issue with making the NOT NULL implicit
> in a PRIMARY KEY specification (per spec but unlike DB2)?
> -- 
> Jeremy

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