Re: [HACKERS] PostGreSQL v6.2.1 for Linux Alpha - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: [HACKERS] PostGreSQL v6.2.1 for Linux Alpha
Date
Msg-id 199802121652.LAA27218@candle.pha.pa.us
Whole thread Raw
In response to Re: [HACKERS] PostGreSQL v6.2.1 for Linux Alpha  ("Kenji T. Hollis" <khollis@Gawain.Houston-InterWeb.COM>)
List pgsql-hackers
>
> Bruce:
>
> > OK, I have a new idea.  See in utils/hash/hashfn.c:tag_hash, there is
> > the line:
> >
> >             for (; keysize > (sizeof(int) - 1); keysize -= sizeof(int),key++)
> >                 h = h * PRIME1 ^ (*key);
> >
> > Now, since h is a long, shouldn't the for loop be comparing
> > sizeof(long)?  However, key is an int*.
>
> How is this a problem?  *key is getting the value of the current pointer
> of key.  This means, if key contains a string: "Ooga" and key++, then the
> value of *key would be "o" in decimal.  This is a standard hashing
> routine, and the problem does not lie here as far as I can see.

You are right.

--
Bruce Momjian
maillist@candle.pha.pa.us

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