Hi,

> > > > Index IDX_LOGSHIFTNUM (1)
> > > > Depth: 3, leaf buckets: 1149, nodes: 179393
> > > > Average data length: 0.00, total dup: 179090, max dup: 1400
> > >
> > >179090 duplicates out of 179393 nodes is a lot i would drop this index
> > >unless there a very specic reason for.
> >
> >Interesting - I dropped this index, and the result was that it took a sp
> >from seconds to minutes ... I will have to investigate why ...
>
> I wouldn't have said this index needed dropping, out of hand. You have no
> way of knowing how the dups are distributed, but max dup is relatively
> small (less than 0.8 %) suggesting they might be quite even. 1400 isn't a
> dreadfully long chain; that still leaves 300 nodes that have single
> entries and the rest distributed across (potentially) 88,000 other
> nodes...probably less, but maybe still quite selectively. Before ditching
> the index, I'd query the table to see just how bad the distribution is.
>
> Helen

Yup as always Helen is right here, i didn't take enough attention to the
max. dup value :-/. How closer the max. dup value to the nr. of nodes the
worser the index is usefull.

Regards,
Arno Brinkman
ABVisie

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