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Re: Creating Histograms

From: Niall Litchfield <>
Date: Thu, 22 Jul 2004 20:55:53 +0100
Message-ID: <>

Comments as always
On Thu, 22 Jul 2004 10:37:21 -0400, Freeman, Donald <> wrote:
> OK, I understand your point about gathering on schedule. I'm moving into =
> taking over a turn-key contractor developed system. We are doing =
> stats/computed every day. We only add, at most, a few thousand records =
> a day. This is much, much less than 10%. We converted a few million =
> records, about five years worth of records, from four or five other =
> public health databases but our daily accrual is relatively small. I =
> probably wouldn't have to run stats once in a month.

take note of how many records you add to relatively *small* tables. 13 rows added to one of our tables caused hell until we gathered stats again (and it took ages for anyone to admit that anything ahd changed). That would be 13 rows in the sense of another financial year to add to the 2 existing ones - so hardly significant at all :).

I guess I'm saying different objects might have different stats needs.

>We also don't =
> collect system stats. I'm hoping to get enough information here to 'have =
> a meeting' and get all of that changed, the method and rate of =
> collection.

Test system stats carefully (I'm probably too cautious on this), but system stats are likely to make quite a noticeable difference to execution times. It is, I'm increasingly convinced, the *right* thing to do. It doesn't mean that you may not have adverse effects. Overall system stats have been positive for our test financial environmentenough  so that they get introduced with the next software upgrade that is running there - but there has been the odd hiccup.

Niall Litchfield
Oracle DBA
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Received on Thu Jul 22 2004 - 14:52:38 CDT

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