17.10 - Implicit DATE-to-UDT Conversion - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - Data Types and Literals

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1143-171K
Language
English (United States)

Performing an implicit data type conversion requires that an appropriate cast definition (see Usage Notes) exists that specifies the AS ASSIGNMENT clause.

SQL Engine performs implicit DATE-to-UDT conversions for the following operations:
  • UPDATE
  • INSERT
  • Passing arguments to stored procedures, external stored procedures, UDFs, and UDMs
  • Specific system operators and functions identified in other sections of this document, unless the DisableUDTImplCastForSysFuncOp field of the DBS Control Record is set to TRUE

If no DATE-to-UDT implicit cast definition exists, Vantage looks for other cast definitions that can substitute.

IF the following combination of implicit cast definitions exists … THEN SQL Engine
Numeric-to-UDT Character-to-UDT

a non-CLOB character type

 
X   uses the Numeric-to-UDT implicit cast definition.

If multiple Numeric-to-UDT implicit cast definitions exist, then SQL Engine returns an SQL error.

  X uses the Character-to-UDT implicit cast definition.

If multiple Character-to-UDT implicit cast definitions exist, then SQL Engine returns an SQL error.

X X reports an error.

Substitutions are valid because Vantage can implicitly cast a DATE type to the substitute data type, and then use the implicit cast definition to cast from the substitute data type to the UDT.