Using COLLECT STATISTICS | Teradata Vantage - 17.10 - Why You Need To Collect Statistics - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Data Definition Language Detailed Topics

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1184-171K
Language
English (United States)

The purpose of collecting statistics is to compute statistical data that the Optimizer uses to optimize table access and join plans. The computed statistical data is retained in a synopsis data structure that is stored in the data dictionary for use during the optimizing phase of SQL request parsing.

Accurate demographics enable the Optimizer to determine the least costly access and join plans for a query. Accurate table demographic information is especially important when data to be accessed using a column or index might be skewed.