Restrictions - Analytics Database - Teradata Vantage

SQL Functions, Expressions, and Predicates

Deployment
VantageCloud
VantageCore
Edition
Enterprise
IntelliFlex
VMware
Product
Analytics Database
Teradata Vantage
Release Number
17.20
Published
June 2022
Language
English (United States)
Last Update
2024-01-12
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lifecycle
latest
Product Category
Teradata Vantageā„¢
If CASE_N is used in a PARTITION BY phrase, it:
  • Can specify a maximum of 65533 conditions (unless it is part of a larger partitioning expression)
  • Must not contain the system-derived columns PARTITION or PARTITION#L1 through PARTITION#L15
  • Must not use Period data types, but can use the following:
    • BEGIN bound function for which input is a Period data type column and not a Period expression.
    • END bound function for which input is a Period data type column and not a Period expression.
    • IS [NOT] UNTIL_CHANGED.
    • IS [NOT] UNTIL_CLOSED.

If CASE_N is used in a partitioning expression for a multilevel PPI, it must define at least two partitions.

Note that partition elimination for queries is often limited to literal or using value equality conditions on the partitioning columns, and the Optimizer may not eliminate some partitions when it possibly could. Also, evaluating a complex CASE_N may be costly in terms of CPU cycles and the overhead of CASE_N may cause the table header to be excessively large.