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From Knut Anders Hatlen <Knut.Hat...@Sun.COM>
Subject Re: Test case in orderby.out file
Date Thu, 29 Apr 2010 18:23:24 GMT
On 04/29/10 05:16 PM, Nirmal Fernando wrote:
> Hi All,
> I think behaviour of following test is not valid, since
> ColumnReference age is not there in the distinct list.
> line:1810 of orderby.out
> ij> -- Ordering by an expression involving an unselected column is not. However,
> -- Derby does not currently enforce this restriction. Note that the answer
> -- that Derby returns is incorrect: Derby returns two rows with duplicate
> -- 'name' values. This is because Derby currently implicitly includes the
> -- 'age' column into the 'distinct' processing due to its presence in the
> -- ORDER BY clause. DERBY-2351 and DERBY-3373 discuss this situation in
> -- more detail.
> select distinct name from person order by age*2;
> ----------
> John
> Mary
> John
> Can someone explain this behaviour?

Hi Nirmal,

I think this test case only attempts to demonstrate a bug that later was
logged as DERBY-4371. If you fix DERBY-4371, I find it quite reasonable
to update orderby.out to reflect that the query is now rejected.

Knut Anders

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