于 2013-09-04 19:30, Noah Misch 回复:
On Wed, Sep 04, 2013 at 12:08:48PM +0800, wangs...@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 <n...@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.
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