Comments on: secondary school mathematics that was almost useful http://www.hackinghat.com/index.php/database/secondary-school-mathematics-that-was-almost-useful Tue, 20 Jul 2010 09:51:44 +0000 http://wordpress.org/?v=2.9.2 hourly 1 By: Steve Knight http://www.hackinghat.com/index.php/database/secondary-school-mathematics-that-was-almost-useful/comment-page-1#comment-1230 Steve Knight Thu, 18 Oct 2007 06:32:40 +0000 http://www.hackinghat.com/?p=3#comment-1230 Just thought I'd add something to this. I was just showing a colleague this particular trick in SQL Server 2005 when it didn't work. I scratched my head and figured I was missing something. He pointed out that for a fractional 'value' you need to be careful of functions like POWER(). They return their results in the same precision as the first argument. Thus: <pre><code>SELECT POWER(10, SUM(LOG10(value)))</code></pre> Will return a result with no decimal places!! It should really be: <pre><code>SELECT POWER(CONVERT(NUMERIC(18,8), 10), SUM(LOG10(value)))</code></pre> Thanks! Just thought I’d add something to this. I was just showing a colleague this particular trick in SQL Server 2005 when it didn’t work. I scratched my head and figured I was missing something. He pointed out that for a fractional ‘value’ you need to be careful of functions like POWER(). They return their results in the same precision as the first argument. Thus:

SELECT POWER(10, SUM(LOG10(value)))

Will return a result with no decimal places!! It should really be:

SELECT POWER(CONVERT(NUMERIC(18,8), 10), SUM(LOG10(value)))

Thanks!

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