Using Oracle TRIM Function.

Oracle TRIM function are used to remove all specific characters either from the beginning, ending or both side of strings.

Note :- trim set should have only one character.

Syntax :
----------
TRIM( [ [ LEADING | TRAILING | BOTH ] trim_character FROM ] string )

LEADING :- Remove trim_character from the front of string.

TRAILING :- Remove trim_character from the end of string.

BOTH :- Remove trim_character from the both (start and end) side of string.

SQL> SELECT TRIM('K' FROM 'KINKGK') RESULT FROM DUAL;

RESU
----
INKG

SQL> SELECT TRIM( LEADING 'K' FROM 'KINKGK') RESULT FROM DUAL;

RESUL
-----
INKGK

SQL> SELECT TRIM( BOTH 'K' FROM 'KINKGK') RESULT FROM DUAL;

RESU
----
INKG

SQL> SELECT TRIM( TRAILING 'K' FROM 'KINKGK') RESULT FROM DUAL;

RESUL
-----
KINKG

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