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From Rick Hillegas <rick.hille...@oracle.com>
Subject Re: Feedback index.html
Date Tue, 24 May 2011 13:07:40 GMT
On 5/22/11 1:43 AM, "Hubert jun. Hölzl" wrote:
> Hi,
>
> I've found a misstake in your documentation at
>
> http://db.apache.org/derby/docs/10.2/ref/rrefsqlj57522.html
>
> There you say
>> A LEFT OUTER JOIN B is equivalent to B RIGHT OUTER JOIN A, with the columns in a
different order
I think that the documentation is trying to express the fact that the 
column order in the ResultSets is different even though the contents of 
the ResultSets would be identical if you permuted the columns into the 
same order. The following script shows this:

ij> connect 'jdbc:derby:memory:db;create=true';
ij> create table A( c int, a int );
0 rows inserted/updated/deleted
ij> create table B( c int, b int );
0 rows inserted/updated/deleted
ij> select * from A left outer join B on A.c = B.c;
C          |A          |C          |B
-----------------------------------------------

0 rows selected
ij> select * from B right outer join A on B.c = A.c;
C          |B          |C          |A
-----------------------------------------------

0 rows selected

Hope this is useful,
-Rick
> But I think it has to be
>> A LEFT OUTER JOIN B is equivalent to B RIGHT OUTER JOIN A, with the tables in a different
order
> Hope it helped,
> Hölzl


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