On August 3, 2002 12:54 am, Jason Stechschulte wrote:
> On Sat, Aug 03, 2002 at 01:49:10AM -0300, Manuel Lemos wrote:
> > >Google has 1 billion pages and qurys in a few milliseconds...
> >
> > Real search engines do not use SQL databases.
> What do search engines use?  Is there something out there that explains
> how they work?

Generally search egines use various hash algorithms to store their data, such 
as B-trees, Hash Tables, etc... Even that, is not enough when dealing with an 
extremely large dataset, in which case expensive hardware is used to provide 
the necessary IO capacity to allow for fast look ups. If you are trully 
interested in how search engines do this, there are plenty of articles 
describing Google's setup in terms of hardware.

As far as fetching data from large MySQL databases it is not impossible or 
slow as some people claim. I have a 4 million record database in MySQL that 
is routinely accessed and most queries on that table are completed in 
0.01-0.03 seconds, speed mostly depending on the number of rows retrieved. 
Keep in mind that your system and database configuration will play a very 
large role in regard to performance once you go beyond a certain amount of 

Ilia Alshanetsky

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