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From Daniel John Debrunner <...@apache.org>
Subject Re: comparisons are not supported for long varchar datatype
Date Fri, 10 Nov 2006 19:47:22 GMT
Craig L Russell wrote:
> Hi Sisilla,
> LONG VARCHAR is a type typically used for BLOBs: images, large 
> documents, graphics, and the like. So it's inappropriate for a primary 
> key or unique or indexed column.

LONG VARCHAR is a character type (not binary) and Derby treats it as a 
large object character string like CLOB. Section of the SQL 
standard 2003 (foundation) basically states that such types are not 
comparable and cannot be used in <unique constraint definition> which 
includes primary keys.

> Are you sure that EmployeeID is a large object? Or perhaps it should be 
> an integer or other integral type.

I think that's the key question, why is LONG VARCHAR being used here?


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