RE: Is this data skewed?

Cherie:

>My question is this: In general, this data appears to
>be fairly well-distributed. However, does the fact that
>for each Saturday and Sunday there are zero rows
>mean that this data is skewed? Might this column be

It depends. My gut would say no. But the real test would be a statistical one. You must look at the distribution of the data in the column and compare it against a theoretical normal distribution. My criterion is that if the data distribution is different from the theoretical norm by more than 2 standard deviations, I consider it skewed and consider it a candidate for a histogram. Again, a good candidate is also one that is used in a where clause of a commonly-used query as a literal predicate.

Hope this helps.

--

Jon Walthour, OCDBA
Oracle DBA
Computer Horizons
Cincinnati, Ohio
 




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