Hi Ravi, In Teradata, SUBSTR function returns a zero length string if start position for extraction is greater than string length and length of extraction is greater than 0.
Also, In Teradata, SUBSTR is a Teradata extension to the ANSI SQL-2003 standard. The same goes for Oracle. Hence the difference in the result. I'm not sure if SUBSTRING function is available on Oracle, though it's available on Teradata and is ANSI SQL-2003 standard compliant.