Re: Collect frequency statistics for arrays

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От Alexander Korotkov
Тема Re: Collect frequency statistics for arrays
Дата
Msg-id CAPpHfdtPPkVS-rKc7=9FU3drDm3LquvTJF8WkDXcCxxqWKciow@mail.gmail.com
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Ответ на Re: Collect frequency statistics for arrays  (Tom Lane <tgl@sss.pgh.pa.us>)
Ответы Re: Collect frequency statistics for arrays
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On Sun, Mar 4, 2012 at 5:38 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
1. I'm still unhappy about the loop that fills the count histogram,
as I noted earlier today.  It at least needs a decent comment and some
overflow protection, and I'm not entirely convinced that it doesn't have
more bugs than the overflow issue.

Attached patch is focused on fixing this. The "frac" variable overflow is evaded by making it int64. I hope comments is clarifying something. In general this loop copies behaviour of histogram constructing loop of compute_scalar_stats function. But instead of values array we've array of unique DEC and it's frequency. 

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With best regards,
Alexander Korotkov.
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