Data Block Selectivity | Teradata Vantage - Data Block Selectivity - Advanced SQL Engine - Teradata Workload Management

Teradata Vantageā„¢ - Workload Management User Guide

Product
Advanced SQL Engine
Teradata Workload Management
Release Number
17.05
17.00
Published
June 2020
Language
English (United States)
Last Update
2021-01-22
dita:mapPath
nbl1556236178169.ditamap
dita:ditavalPath
lze1555437562152.ditaval
dita:id
B035-1197
lifecycle
previous
Product Category
Software
Teradata Vantage

Use the data block selectivity criterion (the percentage of the table the request accesses) to give more resources to requests that access a small subset of the table. For example, you can send a request doing a full-table scan against a large table to a low-priority workload, and send a request accessing only one partition (1/200th of the table) to a high-priority workload.

Data block selectivity is particularly useful on large partitioned tables, but it is also useful for nonpartitioned tables.