Oracle 21c

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CREATE TABLE table_name (value CLOB);
INSERT INTO table_name (value) VALUES (
  XMLQuery(
    'copy $i := $p1
    modify (delete nodes ($i//@onclick, $i//@ondblclick, $i//@onmouseover, $i//@onkeypress))
    return $i'
    PASSING XMLTYPE('<html><p>This is <a href="http://www.test.com" rel="noopener noreferrer" target="_blank">www.test.com</a></p><p>ffffff</p><p><br /></p><p><br /></p><p>Review at <a href="http://www.1159pm.com" rel="noopener noreferrer" target="_blank" onclick="alert()" ondblclick="alert()" onmouseover="alert()" onkeypress="alert()">www.1159PM.com</a> </p><p>fffffff</p></html>')
      AS "p1"
    RETURNING CONTENT
  ).getClobVal()
)
1 rows affected

SELECT * FROM table_name;


VALUE


<html><p>This is <a href="http://www.test.com" rel="noopener noreferrer" target="_blank">www.test.com</a></p><p>ffffff</p><p><br/></p><p><br/></p><p>Review at <a href="http://www.1159pm.com" rel="noopener noreferrer" target="_blank">www.1159PM.com</a></p><p>fffffff</p></html>