On Wed, Oct 29, 2014 at 4:28 PM, Staffan Tylen <staffan.ty...@gmail.com>
wrote:

> But if several rows have the same a value as the max value then the b value
> will be arbitrary, or?
>

Then b will be from one of the rows for which a is maximal - but you don't
know which one.

Similarly, if you say:

    SELECT max(a), max(c), min(d), max(e+f), b FROM table WHERE ...;

Then the b value will be from one of the rows where either a was maximal or
c was maximal or d was minimal or e+f was maximal - but if there are
multiple rows that meet that criterion, you don't know which row you'll get.



>
> Staffan
>
>
> On Wed, Oct 29, 2014 at 7:43 PM, Richard Hipp <d...@sqlite.org> wrote:
>
> > On Wed, Oct 29, 2014 at 2:38 PM, Baruch Burstein <bmburst...@gmail.com>
> > wrote:
> >
> > > Hi,
> > >
> > > If I have a table, "t", with 2 columns, "a" and "b". Assuming that "a"
> > is a
> > > unique number, will the following query always return the whole row
> (that
> > > is, with the correct "b" column) where "a" is the highest number below
> > 50?
> > >
> > > SELECT max(a), b FROM t WHERE a<50;
> > >
> > >
> > That is what it is suppose to do, yes.
> >
> > Note that SQL is unique among SQL database engines in supporting this
> > behavior.  All other SQL database engines (that I know about) will either
> > report the query above as an error, because column b is not in the GROUP
> BY
> > clause and is not inside an aggregate function, or will return b from an
> > arbitrary row, not necessarily the row on which a is maximal.
> >
> > --
> > D. Richard Hipp
> > d...@sqlite.org
> > _______________________________________________
> > sqlite-users mailing list
> > sqlite-users@sqlite.org
> > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
> >
> _______________________________________________
> sqlite-users mailing list
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>



-- 
D. Richard Hipp
d...@sqlite.org
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