17.10 - Limitation: NULL inside Input Strings - Advanced SQL Engine - Teradata Database

Teradata Vantageā„¢ - SQL Functions, Expressions, and Predicates

Advanced SQL Engine
Teradata Database
Release Number
Release Date
July 2021
Content Type
Programming Reference
Publication ID
English (United States)
REGEXP_REPLACE has a limitation in handling ASCII Chr(0), which is NULL. If you concatenate two strings using ASCII Chr(0), REGEXP_REPLACE cannot handle that input string. For example, consider the following code:
sel TD_SYSFNLIB.RegExp_Replace ('a'||chr(0)||'bc', '[b]', 'X', 1, 0) AS 
The function is supposed to replace the b in the input string 'a'||chr(0)||'bc' with X. The result should be a Xc. However, because of the limitation, the result is a.