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Connor McDonald <connor_mcdonald_at_yahoo.com> wrote in message news:<3EDF1BD3.558D_at_yahoo.com>...
> Sybrand Bakker wrote:
> >
> > On 4 Jun 2003 08:11:31 -0700, aoshell2_at_yahoo.com wrote:
> > To reply remove -verwijderdit from my e-mail address
>
> "The same applies to statistics without histograms."
>
> An excessive number of histograms merely serves to pollute the
> dictionary cache and add to parse times...
And don't forget the fact that when using bind variables the
histograms are useless. The plan is only calculated when the qry is
parsed for the first time and all re-executions use the same plan,
regardless off the values of the bind variables. A datawarehous can't
do without histograms. In such an environment it makes no sense to use
bind variables.
In 'my' databases I create histograms for those indexes that have a
large number of leafblocks per key.
Ronald.