Re: What is wrong with hashed index usage?

Michael Loftis wrote:
> The benchmarks will depend mostly on the depth of the Btree.   Hashes 
> will be markedly faster only in the case(s) where descending into the 
> tree to produce a matching leaf node would take longer than walking to 
> the appropriate item in a hash.
> 
> Most of the time until the btree gets deep they are nearly equivalent. 
>  When the tree ends up becoming many levels deep it can take longer to 
> walk than the hash.

And what causes the btree to get deep?  Is it just the number of rows in
the index?

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