Implicit DATE-to-UDT Conversion

Teradata Vantage™ Data Types and Literals

brand
Software
Teradata Vantage
prodname
Teradata Database
Teradata Vantage NewSQL Engine
vrm_release
16.20
category
Programming Reference
featnum
B035-1143-162K

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:
  • 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, 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.