Expressions passed to this function must have the following data types:
- date_timestamp_value = DATE or TIMESTAMP(0)
- day_value = VARCHAR
You can also pass arguments with data types that can be converted to the preceding types using the implicit data type conversion rules that apply to UDFs.
The UDF implicit type conversion rules are more restrictive than the implicit type conversion rules normally used by Vantage. If an argument cannot be converted to the required data type following the UDF implicit conversion rules, it must be explicitly cast.
For details, see Teradata Vantage™ - SQL External Routine Programming, B035-1147.
Since TIMESTAMP values are stored in UTC time within the database and lack a time zone, the session time zone is used to interpret the time stamp value within the function. For TIMESTAMP WITH TIME ZONE values, the time zone component is used to interpret the time stamp value within the function.