Re: [zzdev] Oooops big problem in zigzag implementation

[Andrew Pam <xanni@xxxxxxxxxxxxxxxxx>]

On Thu, Oct 29, 1998 at 03:47:08PM -0500, Mark-Jason Dominus wrote:
> There is no efficient way to find out what links there are from a
> particular cell.  You have to grovel over the entire database looking
> for the links.

Well, it's not quite as bad as that; you only have to try every dimension
to see which ones have a link.  However once there are a very large number
of dimensions this becomes quite inefficient.  One simple solution I have
considered is changing from a hash database to a database with ordered
indexes such as a B-tree (trivial change to use the existing DB database
in B-tree mode instead of hash mode).  This trades off the speed of
insertions and retrievals gained with a hash database against improved
speed of finding all the links from a cell.  At present the former is
far more common than the latter, so this might be counter-productive.

Cheers,
	*** Xanni ***
-- 
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