Re: bk commit into 5.0 tree (tnurnberg:1.2526) BUG#31227

[Sergei Golubchik]

Hi!

On Oct 04, Georgi Kodinov wrote:
> On 04.10.2007, at 08:49, Tatjana A Nuernberg wrote:
> 
> >ChangeSet@stripped, 2007-10-04 07:49:08+02:00,  
> >tnurnberg@stripped +3 -0
> >  Bug#31227: memory overrun with decimal (6,6) and zerofill and  group_concat
> >
> >  This is a pathological case.
> >  DECIMAL(a,b) == a digits altogether, of which b are fractional.
> >  DECIMAL(5,3)    123.45, or -123.45(!)
> >
> >  This requires a characters,
> >  plus one extra for sign,
> >  plus one for decimal point if b>0,
> >  *plus* one extra for a leading '0' if a==b:
> >
> >  DECIMAL(6,6)  -0.123456:
> >  (sign) (zero) (point) (6 decimal places) (\0)
> >
> >  This leading '0' was not factored in.
> 
> This would fit ideally to the function comment.
> If you insist on having it as a commit comment please add: "Fixed  
> by ...." (counting the leading '0' when it's the only digit before  
> the decimal point).

I agree with Georgi. What about a shorter changseset comment
(which, as you remember is like an abstract of a article, not a complete
article):

 Bug#31227: memory overrun with decimal (6,6) and zerofill and group_concat
 Reserve the space for the leading 0 (before the decimal point) in DECIMAL(a,a)

this concisely describes the problem and a fix without explaining the
semantics of DECIMAL(M,N).
 
Regards / Mit vielen Grüssen,
Sergei

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