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From:Steve Meyers Date:October 23 2001 5:57pm
Subject:RE: Length limit of 500 on primary keys?
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> I am not understanding why having a hash and the full url in the 
> database would not take care of the collisions.  Even if you had 
> 10 collisions for a 16 bit hash (say), if your query was:
> SELECT ... WHERE hash=thehashvalue AND url='theurl' you would get 
> very fast lookups on the hash and the url comparison would not 
> add much to the query at that point.  You could even do a partial 
> index on the url, e.g.  "KEY( hash, url(200))".
> 
> b.
> 

That would work, but it was my understanding that they want the key itself to take care of
uniqueness.  If not, then you can do it that way.  However, I would not include part of
the URL in the index -- see my previous message about the key buffer.

Steve Meyers


Thread
Length limit of 500 on primary keys?Shankar Unni21 Oct
  • RE: Length limit of 500 on primary keys?Chris Bolt21 Oct
    • RE: Length limit of 500 on primary keys?Steve Meyers21 Oct
      • Re: Length limit of 500 on primary keys?Shankar Unni22 Oct
        • RE: Length limit of 500 on primary keys?Steve Meyers22 Oct
          • Re: Length limit of 500 on primary keys?Jeremy Zawodny23 Oct
            • RE: Length limit of 500 on primary keys?Steve Meyers23 Oct
              • RE: Length limit of 500 on primary keys?Steve Meyers23 Oct
                • Re: Length limit of 500 on primary keys?Shankar Unni24 Oct
              • Re: Length limit of 500 on primary keys?Bill Adams23 Oct
                • RE: Length limit of 500 on primary keys?Steve Meyers23 Oct
              • RE: Length limit of 500 on primary keys?Don Read23 Oct
            • Re: Length limit of 500 on primary keys?Dan Nelson24 Oct
Re: Length limit of 500 on primary keys?Heikki Tuuri23 Oct