Re: Is it necessary to rewrite table while increasing the scale ofdatatype numeric???

于 2013-09-04 19:30, Noah Misch 回复:
> On Wed, Sep 04, 2013 at 12:08:48PM +0800, wangshuo@highgo.com.cn
> wrote:
>> I find that it takes a long time when I increase the scale of a
>> numeric
>> datatype.
>> By checking the code, I found that's because it needs to rewrite
>> that
>> table's file.
>> After checking that table's data file, I found only parameter
>> n_header
>> changed.
>> And, I found the data in that numeric field never changed.
>> So I thank It's not necessary to rewrite the table's file in this
>> case.
>

Noah Misch <noah@leadboat.com> wrote:
> n_header is part of the numeric field's data.  That's not just
> pedantry: the
> display scale stored in n_header affects how numeric_out() formats
> the value.

Thanks for your reply.

Just because of what you said, I think increasing scale only lead to
differently
diaplay. There's no difference between 5.25 and 5.2500 in use.
So thers's no need to rewrite the table.