REGEXP REPLACE
From Oracle FAQ
REGEXP_REPLACE is an SQL function that can do string replacements based on a regular expression.
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Examples
Replace all letter O's with the number 0:
SELECT REGEXP_REPLACE(col1, 'O', '0') FROM tab1;
Remove all special (unprintable) characters from a string:
SELECT REGEXP_REPLACE(col1, '[:cntrl:]', ' ') FROM tab1;
