BEGIN/END e CREATE Table em um único arquivo .sql

BEGIN     
     EXECUTE IMMEDIATE 'DROP TABLE symbols'; 
EXCEPTION     
  WHEN OTHERS THEN         
   IF SQLCODE != -942 THEN     
 --here you have to write something for this exception
 -- if you don't have any activity to do then you can use NULL (atleast)
 -- you can't put this if statement body empty in oracle
 NULL;
END IF; 
END; 
/