ASCIISTR takes as its argument a string, or an expression that resolves to a string, in any character set and returns an ASCII version of the string in the database character set. Non-ASCII characters are converted to the form \xxxx, where xxxx represents a UTF-16 code unit.
See Also:
Oracle Database Globalization Support Guide for information on Unicode character sets and character semanticsThe following example returns the ASCII string equivalent of the text string "ABÄCDE":
SELECT ASCIISTR('ABÄCDE')
FROM DUAL;
ASCIISTR('
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AB\00C4CDE