Oracle / JDBC: retrieving TIMESTAMP WITH TIME ZONE value in ISO 8601 format

Question

A lot have been said (and written on SO) on parts of the subject, but not in a comprehensive, complete way, so we can have one \"ultimate, covering-it-all\" solution for eve

Answer 1

A slight improvement to #2:

CREATE OR REPLACE PACKAGE FORMAT AS
  FUNCTION TZ(T TIMESTAMP WITH TIME ZONE) RETURN VARCHAR2;
END;
/
CREATE OR REPLACE PACKAGE BODY FORMAT AS
  FUNCTION TZ(T TIMESTAMP WITH TIME ZONE) RETURN VARCHAR2
  AS
  BEGIN
    RETURN TO_CHAR(T,'YYYYMMDD"T"HH24:MI:SS.FFTZHTZM');
  END;
END;
/

The in SQL this becomes:

SELECT FORMAT.TZ(tstz) EVENT_TIME ...

It's more readable.
If you ever need to change it, it's 1 place.
The downside is it is an extra function call.