For example: There is a table of one column is having data like
common
c
o
m
m
o
n
For the posted sample data this'll do ya:
select substr(col1, level, 1)
from t23
connect by level <= length(col1)
/
If your real need is more complicated then you must post a realistic use case. If you simply have more than one row of data in your table then MT0's recursive WITH clause solution is the way to go (assuming you are on 11gR2 or higher)