Change comma to period

Question

Hi.
I'm looking for a method to change all occurences of comma into period of a column.
Its formatted number(18,4)
I have tried:
update table
set column = replace (column, chr(44), chr(46)
where column like chr(44)
No luck
Nicolai

Answer 1

Hi Nicolai,
If the column is of NUMBER datatype the comma or the period isn't really stored there.
The NLS_ settings just controls how it default displayed when displayed as a string.
If the column does containt numbers, only you should never change it into varchar2.
On my system I have:
SQL> select 'DATABASE' level_, parameter, value
  from nls_database_parameters
where parameter in ('NLS_LANGUAGE', 'NLS_NUMERIC_CHARACTERS')
union all
select 'INSTANCE', parameter, value
  from nls_instance_parameters
where parameter in ('NLS_LANGUAGE', 'NLS_NUMERIC_CHARACTERS')
union all
select 'SESSION', parameter, value
  from nls_session_parameters
where parameter in ('NLS_LANGUAGE', 'NLS_NUMERIC_CHARACTERS')
LEVEL_   PARAMETER                      VALUE                                  
DATABASE NLS_LANGUAGE                   AMERICAN                               
DATABASE NLS_NUMERIC_CHARACTERS         .,                                     
INSTANCE NLS_LANGUAGE                   AMERICAN                               
INSTANCE NLS_NUMERIC_CHARACTERS                                                
SESSION  NLS_LANGUAGE                   DANISH                                 
SESSION  NLS_NUMERIC_CHARACTERS         ,.                                     
6 rows selected.So I get (Since the database and instance settings are written over at session level):
SQL> select 1.2 from dual
       1.2
       1,2
1 row selected.If I want to change it I can
SQL> select to_char(1.2, '9.0') from dual
TO_C
1.2
1 row selected.Or
SQL> alter session set NLS_NUMERIC_CHARACTERS = '.,'
Session altered.
SQL> select 1.2 from dual
       1.2
       1.2
1 row selected.Regards
Peter