With out Using Like Function

substr(name,1,1)='S' and
substr(name,-1)='N'

Instr(name,'S')= 1 and
Instr(name,'N')= length(name)

'S'||Substr(name,2,length(name)-1)||'n' = name

11) How to find Duplicate Records

   select * from emp where rowid not in ( select min(rowid) from emp group by ename);