16.20 - Implicit DATE-to-UDT Conversion - Teradata Vantage NewSQL Engine

Teradata Vantage™ Data Types and Literals

Teradata Database
Teradata Vantage NewSQL Engine
March 2019
Programming Reference

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

Teradata Database performs implicit DATE-to-UDT conversions for the following operations:
  • 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, Teradata Database looks for other cast definitions that can substitute.

IF the following combination of implicit cast definitions exists … THEN Teradata Database …
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 Teradata Database returns an SQL error.

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

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

X X reports an error.

Substitutions are valid because Teradata Database 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.