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Message Posted: Thu, 18 Nov 2004 @ 16:07:52 GMT

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First the negative numbers -
The problem of negative numbers in the Time estimates was corrected in version 4.1.0.2 of the Monitor Object which was a part of the Teradata Manager 6.1.0.2 efix. (available from the patch server.)

The big difference between Estimates and Actuals is (hopefully) only occuring when the confidence level is low. (or None)

If you see big differences when the confidence level is high you should probably report that to the GSC.

When confidence is low, the system will be using random amp samples to estimate its numbers. If a few tables are being joined, (this and previous steps) all with low confidence, the estimates can rapidly diverge from the actual value. (Each error is multiplied by that of the next step)

Mike Dempsey
Teradata Client Tools

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