Constrained (Slow Path) DELETE Processing - Teradata Database - Teradata Vantage NewSQL Engine

SQL Data Manipulation Language

Product
Teradata Database
Teradata Vantage NewSQL Engine
Release Number
16.20
Published
March 2019
Language
English (United States)
Last Update
2019-05-03
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B035-1146
lifecycle
previous
Product Category
Teradata Vantage™
The processing time for a constrained delete (DELETE...WHERE) can increase when:
  • The DELETE does not meet the conditions for a fastpath delete processing. See Unconstrained Fastpath Delete Processing.
  • The FALLBACK option is specified for the table, because the rows in the secondary copy of the table must also be deleted.
  • Secondary indexes are defined for the table, because the secondary index subtable also must be updated to account for the rows deleted.

Processing time for a constrained delete can be shortened by specifying a primary index value, a USI value, or a highly selective NUSI value as the conditional expression of the WHERE clause.