Determining if a data is an integer or not?

[raghud]

I am not clear what you want ..
Extract second char and
and use any number function to find it is number or not
If not number it will error out
example
select abs(itmid) from ccs_orders where rownum < 2
*
ERROR at line 1:
ORA-01722: invalid number

If it is number

SQL> select abs(acweek) from ccs_orders where rownum < 2;

ABS(ACWEEK)
-----------
1