Oracle SQL Developer : Formatting Query Results to CSV/xml/html/json

Add hint to sql in the below format to get custom and run in execute mode (F5)

SELECT /*csv*/ * FROM scott.emp;
SELECT /*xml*/ * FROM scott.emp;
SELECT /*html*/ * FROM scott.emp;
SELECT /*delimited*/ * FROM scott.emp;
SELECT /*insert*/ * FROM scott.emp;
SELECT /*loader*/ * FROM scott.emp;
SELECT /*fixed*/ * FROM scott.emp;
SELECT /*text*/ * FROM scott.emp;

SELECT /*json*/ * FROM scott.emp;

or

SET SQLFORMAT csv

SET SQLFORMAT json