On Wed, Aug 15, 2012 at 12:14 PM, Heikki Linnakangas < heikki.linnakan...@enterprisedb.com> wrote:
> Histogram of upper bounds would be both more >> accurate and natural for some operators. However, it requires collecting >> additional statistics while AFAICS it doesn't liberate us from having >> histogram of range lengths. >> > > Hmm, if we collected a histogram of lower bounds and a histogram of upper > bounds, that would be roughly the same amount of data as for the "standard" > histogram with both bounds in the same histogram. Ok, we've to decide if we need "standard" histogram. In some cases it can be used for more accurate estimation of < and > operators. But I think it is not so important. So, we can replace "standard" histogram with histograms of lower and upper bounds? ------ With best regards, Alexander Korotkov.
