Benefits of Multiple-Input Functions - Aster Execution Engine

Teradata Aster® Developer Guide

Product
Aster Execution Engine
Release Number
7.00.02
Published
July 2017
Language
English (United States)
Last Update
2018-04-13
dita:mapPath
xnl1494366523182.ditamap
dita:ditavalPath
Generic_no_ie_no_tempfilter.ditaval
dita:id
ffu1489104705746
lifecycle
previous
Product Category
Software

Some benefits of multiple-input SQL-MapReduce functions over single-input functions that produce the same output are:

  • Prediction functions that use trained models have better performance and security.

    A multiple-input prediction function takes the model as a dimensional input, and one or more data inputs to which to apply the model.

  • Their inputs need not share a common schema.
  • They avoid the joins, unions, and creation of temporary tables their single-input counterparts need.
  • They facilitate creating new types of analytic functions (for example, multichannel attribution).
  • They use memory better, because:
    • Partitioning and grouping of tuples occurs before the function operates on them; therefore, less data is processed by the function.
    • One copy of a dimensional input is held in memory and used to operate on all tuples from other inputs.