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From Paul Loy <ketera...@gmail.com>
Subject Re: working with time uuid
Date Mon, 06 Jun 2011 15:52:09 GMT
    private static int compareTimestampBytes(ByteBuffer o1, ByteBuffer o2)
    {
        int o1Pos = o1.position();
        int o2Pos = o2.position();

        int d = (o1.get(o1Pos+6) & 0xF) - (o2.get(o2Pos+6) & 0xF);
        if (d != 0) return d;

        d = (o1.get(o1Pos+7) & 0xFF) - (o2.get(o2Pos+7) & 0xFF);
        if (d != 0) return d;

        d = (o1.get(o1Pos+4) & 0xFF) - (o2.get(o2Pos+4) & 0xFF);
        if (d != 0) return d;

        d = (o1.get(o1Pos+5) & 0xFF) - (o2.get(o2Pos+5) & 0xFF);
        if (d != 0) return d;

        d = (o1.get(o1Pos) & 0xFF) - (o2.get(o2Pos) & 0xFF);
        if (d != 0) return d;

        d = (o1.get(o1Pos+1) & 0xFF) - (o2.get(o2Pos+1) & 0xFF);
        if (d != 0) return d;

        d = (o1.get(o1Pos+2) & 0xFF) - (o2.get(o2Pos+2) & 0xFF);
        if (d != 0) return d;

        return (o1.get(o1Pos+3) & 0xFF) - (o2.get(o2Pos+3) & 0xFF);
    }


Looks like it's only comparing the timestamp bytes.

On Mon, Jun 6, 2011 at 4:06 PM, Patrick Julien <pjulien@gmail.com> wrote:

> How does this work exactly?  If you're using generation 1 time uuids
> for your keys to get ordering, doesn't this mean the keys need to be
> generated all on the same host when you either query or insert?  Or
> does cassandra only inspect the bits that represent the time stamp of
> the UUID when performing a lookup?
>



-- 
---------------------------------------------
Paul Loy
paul@keteracel.com
http://uk.linkedin.com/in/paulloy

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