The best example to follow would be Java implementation of try-catch-finally. However in PL/SQL it would get messy and the code would remind good ol' spaghetti western with epic theme - The Good, The ...
SET DEF ON TERM OFF ECHO ON FEED OFF VER OFF HEA ON LIN 2000 PAGES 100 LONG 8000000 LONGC 800000 TRIMS ON TI OFF TIMI OFF SERVEROUT ON SIZE 1000000 NUMF "" SQLP SQL>; ...