15.00 - Considerations for Basing a Partitioning Expression on a CASE_N Function - Teradata Database

Teradata Database Design

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

Considerations for Basing a Partitioning Expression on a CASE_N Function

Building a partitioning expression on CASE_N is a reasonable thing to do only if the following items are all true:

  • The partitioning expression defines a mapping between conditions and INTEGER numbers.
  • There are limited number of conditions (too many conditions can lead to excessive CPU usage or the table header exceeding its maximum size limit).
  • Your query workloads against the table use equality conditions on the partitioning columns to specify a single partition.
  • You have no need to alter the partitioning of the table.
  • You get the plans and data maintenance you need.