Re: Okay- I give up - what on earth is a "hash" ?

Thank you Jonathan.......given that definition then, would it be accurate to say that a "hash table" would be a table that included the distinct values of a
join field? For example, a hash table where the join field is 'gender' would include only 'male' and 'female'?

I ask because I'm reading that a hash join is often preferred if there is a join column with low cardinality and a large # of rows...it seems that a hash
table would be a table of each distinct value?

Although, after reading Brian's reply maybe I'll just go have lunch :)

"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message news:1016721483.26795.0.nnrp-10.9e984b29_at_news.demon.co.uk...
>
> A hash function or method is a function
> that has a limited list of possible output
> values. When supplied with a large list of
> input values, a good hash function will distribute
> the input randomly, evenly, and reproducibly
> across its list of outputs.
>
> --
> Jonathan Lewis
> http://www.jlcomp.demon.co.uk
>
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Received on Thu Mar 21 2002 - 11:17:08 CST