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From "Mamta Satoor" <msat...@gmail.com>
Subject Re: Collation implementation WAS Re: Should COLLATION attribute related code go in BasicDatabase?
Date Thu, 15 Mar 2007 17:25:07 GMT
Excuse my ignorance, but what does it mean by "order by that spills to the
disk"?

Mamta


On 3/15/07, Mike Matrigali <mikem_app@sbcglobal.net> wrote:
>
>
>
> Daniel John Debrunner wrote:
> > Rick Hillegas wrote:
> >
> >> Daniel John Debrunner wrote:
> >>
> >>> ...
> >>>
> >>> - The collation type (the integer) is written into the meta-data for
> >>> an index just as ascending/descending is today (including the btree
> >>> control row, thus making the information available for recovery).
> >>> Collation type applies to all character columns in the index.
> >>>
> >> This suggests that all of the columns in the index must have the same
> >> collation? I don't think that is powerful enough to support the
> >> full-blown SQL collation language, which allows you to mix differently
> >> collated columns in an ORDER BY clause. Why can't the collation type
> >> be an array of ints just as the sort direction is an array of booleans
> >> in IndexDescriptor?
> >
> >
> > That would be more flexible, but is it required? Is an order by that
> > spills to disk implemented using a BTREE?
>
> No, order by that spills to disk is implemented by the sorter.
>
> >
> > Thanks,
> > Dan.
> >
> >
> >
>
>

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