Thank you John!

I confirmed that this fixes the issue I was experiencing. Your solution of
carrying the sort direction over to other columns makes sense to me,
although I don't remember if it matches what someone familiar with SQL
would expect.

-Will

On Fri, Apr 22, 2016 at 9:57 AM, K. John Wu <[email protected]> wrote:

> Hi, Will,
>
> Thanks for the report.  There was a couple of problem with the
> ordering function that caused this problem you've observed.
>
> - as you've observed, the values of s are all 1s, which causes the
> ordering function attempting to order with other columns.  In this
> process, the ordering flag "DESC" is not carried appropriately.  The
> updated code attempts to keep the option "DESC" when the user has
> specified "DESC" to all order by keys.  In your case, you have one
> order by key and one specification of "DESC", so the "DESC" flag is
> preserved for all sorting operation.  See if you agree with this
> logical and let us know.
>
> - there was another bug in the code that causes the sorting procedure
> itself to only work for ASCENDING order.  This problem was hidden
> because the test case intended to catch this was not thoroughly
> examined until now -- thanks for bring this problem up to our attention.
>
> A fix has been checked into the SVN repository as SVN revision 853.
> Please give it a try when you get the chance.
>
> Thanks again.
>
> John
>
> PS: you can access the source code following the instruction at
> https://code.lbl.gov/scm/?group_id=44
>
>
>
>
>
> On 4/17/16 6:25 PM, Will Glozer wrote:
> > Hello,
> >
> > When FastBit is asked to use descending sort on an aggregation column
> > with 1 distinct value it attempts to sort by all columns and in doing
> > so breaks the row ordering. Here's an example input CSV:
> >
> > 11,43,0
> > 11,43,1
> > 13,43,0
> > 13,43,1
> > 17,43,0
> > 17,43,1
> > 19,43,1
> > 19,97,1
> >
> > Load:
> >
> > `ardea -d test -m "a:int,b:int,c:int" -t test.csv`
> >
> > Query:
> >
> > `ibis -d test -q "select a, b, sum(c) as s from test where 1=1 order
> > by s desc limit 1000"`
> >
> > 19, 43, 1
> > 19, 43, 1
> > 17, 43, 1
> > 13, 43, 1
> > 11, 97, 1
> >
> > Thanks,
> > Will
> >
> >
> >
> > _______________________________________________
> > FastBit-users mailing list
> > [email protected]
> > https://hpcrdm.lbl.gov/cgi-bin/mailman/listinfo/fastbit-users
> >
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