Re: count(*) - sample block

From: Andy Hassall <andy_at_andyh.co.uk>
Date: Fri, 08 Dec 2006 22:41:05 +0000
Message-ID: <g9qjn2pmpkbfmem18639lnltqdtk0ket5m@4ax.com>

On 8 Dec 2006 13:43:33 -0800, "prateek" <hkprateek_at_gmail.com> wrote:

>I am curious to know why this query:
>
>"select count(*) from far_employee sample block (1);"
>
>returns zero at times and some other times returns a non zero number.
>Table: far_employee is populated with more than 400K records.

The blocks sampled probably contained no rows, i.e. they are below the HWM for the table, but not currently populated.

-- 
Andy Hassall :: andy@andyh.co.uk :: http://www.andyh.co.uk
http://www.andyhsoftware.co.uk/space :: disk and FTP usage analysis tool

Received on Fri Dec 08 2006 - 16:41:05 CST