how to convert varchar to number in Oracle

Question

My query is

select num from (
select substr('2*3*4',2) num  from dual)

I am getting '2*3*4' as result after executing but my result should be 24.Can any one please help me in converting it to number.Thanks.

Answer 1

You can use the TO_NUMBER function to convert char/varchar to a number.

You can do the following:

select TO_NUMBER('2')*TO_NUMBER('3')*TO_NUMBER('4') from dual;

Here is a demo.