Rick Hillegas (JIRA) wrote:
WORKAROUND:
You can work around this limitation by rewriting your query
so that the SELECT list does not alias an expression to the
same name as another column or alias. The following rewritten
query works fine:
select a+1 as a, a+1 as c from myTable group by b;
For no apparent reason except that I'm currently reviewing DERBY-883, I noticed
the "b" in this query (which I think was supposed to be a "c"?) and so I tried
it out to see if it would work...
ij> create table myTable (a int, b int);
0 rows inserted/updated/deleted
ij> select a+1 as a, a+1 as c from myTable group by b;
ERROR 42Y36: Column reference 'A' is invalid. For a SELECT list with a GROUP
BY, the list may only contain grouping columns and valid aggregate expressions.
ij> select a+1 as a, a+1 as c from myTable group by c;
ERROR 42X04: Column 'C' is either not in any table in the FROM list or appears
within a join specification and is outside the scope of the join specification
or appears in a HAVING clause and is not in the GROUP BY list. If this is a
CREATE or ALTER TABLE statement then 'C' is not a column in the target table.
ij> select a+1 as a, a+1 as c from myTable group by a;
A |C
-----------------------
0 rows selected
Just curious...am I missing something?
Army
