G-1030: Avoid defining variables that are not used.

Minor

Efficiency, Maintainability

Reason

Unused variables decrease the maintainability and readability of your code.

Example (bad)

CREATE OR REPLACE PACKAGE BODY my_package IS
   PROCEDURE my_proc IS
      l_last_name  employees.last_name%TYPE;
      l_first_name employees.first_name%TYPE;
      co_department_id CONSTANT departments.department_id%TYPE := 10;
      e_good EXCEPTION;
   BEGIN
      SELECT e.last_name
        INTO l_last_name
        FROM employees e
       WHERE e.department_id = co_department_id;
   EXCEPTION
      WHEN no_data_found THEN NULL; -- handle_no_data_found;
      WHEN too_many_rows THEN null; -- handle_too_many_rows;
   END my_proc;
END my_package;
/

Example (good)

CREATE OR REPLACE PACKAGE BODY my_package IS
   PROCEDURE my_proc IS
      l_last_name  employees.last_name%TYPE;
      co_department_id CONSTANT departments.department_id%TYPE := 10;
      e_good EXCEPTION;
   BEGIN
      SELECT e.last_name
        INTO l_last_name
        FROM employees e
       WHERE e.department_id = co_department_id;

      RAISE e_good;
   EXCEPTION
      WHEN no_data_found THEN NULL; -- handle_no_data_found;
      WHEN too_many_rows THEN null; -- handle_too_many_rows;
   END my_proc;
END my_package;
/