15.00 - Guidelines for Handling Standalone Derived Data - Teradata Database

Teradata Database Design

prodname
Teradata Database
vrm_release
15.00
category
User Guide
featnum
B035-1094-015K

Guidelines for Handling Standalone Derived Data

As a general rule, using an aggregate join index or a global temporary table is preferable to denormalizing the physical implementation of the fully normalized logical model.

The following table provides guidelines on handling standalone derived data attributes by denormalization. The decisions are all based on the demographics of the particular data. When more than one recommended approach is given, and one is preferable to the other, the entries are ranked in order of preference.

 

Access Frequency

Change Rating

Update Frequency

Recommended Approach

High

High

Dynamic

1 Use an aggregate join index or global temporary table.

2 Denormalize the physical implementation of the model.

High

High

Scheduled

Use an aggregate join index or global temporary table.

High

Low

Dynamic

Use an aggregate join index or global temporary table.

High

Low

Scheduled

  • Use an aggregate join index or global temporary table.
  • Produce a batch report that calculates the aggregates whenever it is run.
  • Low

    Unknown

    Unknown

    Calculate the information on demand rather than storing it in the database.

    Any time the number of tables and rows involved is small, calculate the derived information on demand.