SELECT first_name 
  FROM hr.employees  
 WHERE regexp_like(first_name,  
     '^('                                     -- globally predefine begin of string  
     || regexp_replace( regexp_replace( 
     'Daniel%|G_ra_d|% %|Patrick|Ste(v|ph)en' -- test pattern using traditional like metacharacters and regexp metacharacters 
     ,'_','.')                                -- replace like metachareacter '_' with regexp pattern '.'  
     ,'%','.*')                               -- replace like metacharacter '%' with regexp pattern '.*'  
     || ')$'                                  -- globally predefine end of string  
 ) 
 ORDER BY first_name