How to spell a numeric value in english words

In a recent topic in the forums there was a question on "how to spell out numeric values in english" and an excerpt from the manuals indicating there is a format for the new TO_CHAR function in TD14: "Any numeric element followed by SP is spelled in English words."

The manuals are a bit misleading, they don't mention that this option is only available for TO_CHAR(DateTime). It's based on Oracle's implementation and indeed embarrassing as year or julian day  are also numeric values, but you can't pass a numeric value, it must be extracted from a DATE.

Teradata's date range is less than Oracle's, so the well-known "julian day" trick TO_CHAR(TO_DATE(numericval,'j'), 'jsp') doesn't work as Oracle's calendar starts on January 1, 4712 BCE, thus the lowest date in Teradata is julian day 1721426 in Oracle:

 BTEQ -- Enter your SQL request or BTEQ command:
SELECT TO_CHAR(DATE '0001-01-01', 'jsp') (VARCHAR(100));

 *** Query completed. One row found. One column returned.
 *** Total elapsed time was 1 second.

TO_CHAR(0001-01-01,'jsp')
---------------------------------------------------------------------
one million seven hundred twenty-one thousand four hundred twenty-six

But based on this knowledge you can apply some modifications to get up to 6 digits:

SEL 123456 AS x,
   CASE
      WHEN x = 0 THEN 'zero'
      ELSE SUBSTRING((TO_CHAR(DATE '0763-09-18' + ABS(x), 'jsp') (VARCHAR(100))) FROM 13)
   END;


 *** Query completed. One row found. 2 columns returned.
 *** Total elapsed time was 1 second.

          x <CASE  expression>
----------- ---------------------------------------------------------------
     123456 one hundred twenty-three thousand four hundred fifty-six

Fiinally add some more calculations to cover the full range of a BIGINT and implement it as a SQL UDF:

REPLACE FUNCTION SpellNumeric (x BIGINT)
RETURNS VARCHAR(220)
LANGUAGE SQL
CONTAINS SQL
NOT DETERMINISTIC
RETURNS NULL ON NULL INPUT
SQL SECURITY DEFINER
COLLATION INVOKER
INLINE TYPE 1
RETURN 
     CASE WHEN ABS(x) >= (1e+15 (BIGINT)) AND (ABS(x) / (1e+15 (BIGINT)) MOD 1000) <> 0 THEN SUBSTRING(TO_CHAR(DATE '0763-09-18' + ABS(x / (1e+15 (BIGINT)) MOD 1000), 'jsp') FROM 13) ||' quadrillion ' ELSE '' END
  || CASE WHEN ABS(x) >= (1e+12 (BIGINT)) AND (ABS(x) / (1e+12 (BIGINT)) MOD 1000) <> 0 THEN SUBSTRING(TO_CHAR(DATE '0763-09-18' + ABS(x / (1e+12 (BIGINT)) MOD 1000), 'jsp') FROM 13) ||' trillion '    ELSE '' END
  || CASE WHEN ABS(x) >= (1e+09 (BIGINT)) AND (ABS(x) / (1e+09 (BIGINT)) MOD 1000) <> 0 THEN SUBSTRING(TO_CHAR(DATE '0763-09-18' + ABS(x / (1e+09 (BIGINT)) MOD 1000), 'jsp') FROM 13) ||' billion '     ELSE '' END
  || CASE WHEN ABS(x) >= (1e+06 (BIGINT)) AND (ABS(x) / (1e+06 (BIGINT)) MOD 1000) <> 0 THEN SUBSTRING(TO_CHAR(DATE '0763-09-18' + ABS(x / (1e+06 (BIGINT)) MOD 1000), 'jsp') FROM 13) ||' million '     ELSE '' END
  || CASE WHEN x = 0 THEN 'zero' ELSE SUBSTRING((TO_CHAR(DATE '0763-09-18' + ABS(x) MOD (1000000 (BIGINT)), 'jsp') (VARCHAR(100))) FROM 13) END
;

SELECT 123456789012345678 (BIGINT) AS x, spellnumeric(x);


 *** Query completed. One row found. 2 columns returned.
 *** Total elapsed time was 1 second.

                   x spellnumeric(x)
-------------------- ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  123456789012345678 one hundred twenty-three quadrillion four hundred fifty-six trillion seven hundred eighty-nine billion twelve million three hundred forty-five thousand six hundred seventy-eight 

Some remarks:

• Sadly, there's no easy way to change the output to another language.
• This function doesn't cover negative values (simply add a CASE WHEN x < 0 THEN 'minus ' ELSE '' END)
• It's based on american english, but could be easily modified to the european numbering scheme (billion = milliard, etc.).  
• And of course it's not tested for the full range of values