16.10 - Collecting Statistics on Skewed Data - Teradata Database

Teradata Database Administration

Product
Teradata Database
Release Number
16.10
Release Date
April 2018
Content Type
Administration
Publication ID
B035-1093-161K
Language
English (United States)

For collecting statistics on skewed data, the Optimizer can accommodate exceptional values. Statistics take into account the most nonunique value in a table and the most nonunique value in a value range.

Without statistics, the system relies on dynamic AMP sampling, which can be quite inaccurate when the table is small or unevenly distributed. Small tables often distribute unevenly.