16.20 - Example: Statistics Are Not Copied When Set Or Aggregation Operators Are Specified In The Query - Teradata Database - Teradata Vantage NewSQL Engine

Teradata Vantage™ SQL Data Definition Language Syntax and Examples

Product
Teradata Database
Teradata Vantage NewSQL Engine
Release Number
16.20
Published
March 2019
Content Type
Programming Reference
Publication ID
B035-1144-162K
Language
English (United States)
Last Update
2019-05-24

Teradata Database does not copy statistics if set operators or aggregation operations are specified in the query as these examples demonstrate.

Example1

In this example, Teradata Database does not copy statistics because of the aggregating GROUP BY clause in the subquery.

    CREATE TABLE t3 (c1, c2) AS (SELECT MAX(x), y
                                 FROM test   
                                 GROUP BY 2) 
    WITH DATA AND STATISTICS;

Example2

In this example, Teradata Database does not copy statistics because of the aggregating GROUP BY clause in the subquery:

    CREATE TABLE t3 (c1, c2) AS (SELECT COUNT(x), y 
                                 FROM test 
                                 GROUP BY 2) 
    WITH DATA AND STATISTICS;

Example3

In this example, Teradata Database does not copy statistics because of the aggregating GROUP BY and HAVING clauses in the subquery.

    CREATE TABLE t3(a, b, c) AS (SELECT x1, MIN(y1), AVG(a1)
                                 FROM test1 
                                 GROUP BY x1 
                                 HAVING AVG(y1) > 40) 
    WITH DATA AND STATISTICS;