Re: table stats

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Fri, 23 Apr 2004 10:25:44 +0000 (UTC)
Message-ID: <c6aqv8$fmt$1@hercules.btinternet.com>

I think you should never trust avg_row_len after any call to dbms_stats.
(method_opt => 'for all indexed columns' also leaves the column with its default value of 100)

Even when it's set "properly", it's likely to be misleading because is omits the 3 byte row header, the two byte rowindex entry
(as does analyze), the length byte for any embedded null columns, and the extra
length bytes needed by columns with content greater than 254 bytes.

Fortunately (from Oracle's perspective) it's not used for anything. Unfortunately (from the DBA perspective) it's sometimes used for capacity planning.

-- 
Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

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"dias" <ydias_at_hotmail.com> wrote in message
news:55a68b47.0404221326.7f0369d5_at_posting.google.com...


> Hi,

>

> In 9.2, the av_row_len is also wrong with method_opt=> null.

>

> Dias

Received on Fri Apr 23 2004 - 05:25:44 CDT