Oracle 23c

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ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';
CREATE TABLE table_name (id, text) AS
  Select 1, '<font face="Microsoft Sans Serif" size="8" color="#000000">ABC 123</font>' FROM DUAL UNION ALL
  Select 2, '<font face="Microsoft Sans Serif" size="8" color="#000000">1 ETG</font>' FROM DUAL UNION ALL
  Select 3, '<font face="Microsoft Sans Serif" size="8" color="#000000">Gatelys PERC</font>' FROM DUAL UNION ALL
  Select 4, '<font face="Microsoft Sans Serif" size="8" color="#000000">Gml TK 144</font>' FROM DUAL UNION ALL
  Select 5, '<font attr=">">XYZ</font>' FROM DUAL;
5 rows affected

SELECT id,
       XMLQUERY('*/text()' PASSING XMLTYPE(text) RETURNING CONTENT) AS text
FROM   table_name;


ID
TEXT


1
ABC 123

2
1 ETG

3
Gatelys PERC

4
Gml TK 144

5
XYZ


SELECT id,
       REGEXP_REPLACE(text, '<.*?>') AS text
FROM   table_name;


ID
TEXT


1
ABC 123

2
1 ETG

3
Gatelys PERC

4
Gml TK 144

5
">XYZ


SELECT id,
       REGEXP_REPLACE(text, q'{<([^"']+?|".*?"|'.*?')+?>}') AS text
FROM   table_name;


ID
TEXT


1
ABC 123

2
1 ETG

3
Gatelys PERC

4
Gml TK 144

5
XYZ