From: Warren Young
Date: October 27 2005 5:54am
Subject: Re: Retrieving 300K+ records
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Alex Vishnev wrote:
> 
> Before I jump
> into mysql C library, can anyone else confirm or deny that overhead of Row
> object (or others) can degrade the performance on large queries? 

Easily.  There are multiple copies of the data made, lots of memory 
being moved around, type conversions, etc.  This is not a low-overhead 
class.

There's an item on the Wishlist to alleviate some of this, and some 
ideas at how to implement it.  All that's wanted is someone interested 
enough to do it in a clean way that doesn't break the ABI.  Or, patience 
to wait until 3.x.