Re: Concatenate numbers

On Jan 2, 3:38 pm, "fitzjarr..._at_cox.net" <fitzjarr..._at_cox.net> wrote:
> On Jan 2, 2:30 pm, Ed Prochak <edproc..._at_gmail.com> wrote:
>
>
>
>
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> > On Jan 2, 2:19 pm, nickli2..._at_gmail.com wrote:
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> > > On Jan 2, 1:49 pm, "fitzjarr..._at_cox.net" <fitzjarr..._at_cox.net> wrote:
>
> > > > On Jan 2, 11:38 am, nickli2..._at_gmail.com wrote:
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> > > > > Hi,
>
> > > > >    I have a table with the following two columns and sample data:
>
> > > > >     tran_date  DATE;
> > > > >     digits        NUMBER;
>
> > > > >     10/2/2007      0.000738889791980111
> > > > >     11/22/2007    0.00083740843091
> > > > >     12/11/2007    6.00083740843091
>
> > > > >     For a special output, I tried to concatenate the two columns using
> > > > > the following SQL:
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> > > > >     SELECT to_char(tran_date,'YYYYMMDD') || ',' || digits from
> > > > > mytable;
>
> > > > >     The result is missing the "0" for two numbers starting with "0."
> > > > > as in the following:
>
> > > > >      20071002,.000738889791980111
> > > > >      20071122,.00083740843091
> > > > >      20071211,6.00083740843091    (This is fine)
>
> > > > >      I know I may be able to do some decode or other manipulation, but
> > > > > could someone tell me why the leading "0" is omitted from the query
> > > > > output?
>
> > > > >     Thanks in advance.
>
> > > > >     Nick
> > []
>
> > > Thanks for your help. Could you tell me why Oracle decides to omit the
> > > leading "0" when concatenating the numbers and what settings affect
> > > this?
>
> > Changing the datatype to VARCHAR seems like overkill. Numeric data
> > should be stored in numeric data types. I would suggest using the
> > correct number format for the output. I think
> > set numformat   0.999999999999999999
> > should work. Or using that format pattern with the column command:
> > column digits format  0.999999999999999999
> > should give your desired result.
>
> > (note: I did not test this pattern, but the syntax of the commands is
> > correct.)
>
> > HTH,
> >   ed- Hide quoted text -
>
> > - Show quoted text -
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> I have tested such a 'fix' and it doesn't do what the OP requests.
> The concatenation operation, along with an implicit conversion, 'lops
> off' the leading 0 (again, as it's not a significant digit).
>
> Preserving the leading 0 is, at least in 10.2.0.3 and earlier
> releases, only possible with the data stored as a varchar2.
>
> David Fitzjarrell

I tested it and it does what he wants. There are two problems though. First it inserts a space before the number, second is that you must have a fixed number of digits after the decimal. The first can be remedied using a substr and the second by using a format mask with the maximum number of decimal places then using rtrim to remove the trailing 0's

SQL> select to_char(sysdate,'YYYYMMDD')||','||to_char(0.8,'0.99999') from dual;

TO_CHAR(SYSDATE,'

SQL> select to_char(sysdate,'yyyymmdd')||','|| rtrim(substr(to_char(0.8,'0.99999'),2),'0') from dual;

TO_CHAR(SYSDATE,'YYYYMMDD')||','||RTR