Analytical function doesn't expect any argument. Rank() itself enough to
sequence based on the window you have defined in partition by. So
Rank() over (partition by cmscustid order by orderdate)
Should work as long as I have wrote right syntax for hive.
Sent via Rocket from my HTC
----- Reply message -----
From: "j.barrett Strausser" <j.barrett.straus...@gmail.com>
To: <user@hive.apache.org>
Subject: Semantics of Rank.
Date: Thu, Jul 25, 2013 1:08 AM
Thanks for the reply. Perhaps my misunderstanding of the relation between
rank and the windowing function is wrong.
What I want to achieve for the following is : For a given customer id,
sort his orders. I thought the below would work.
SELECT eh.cmsorderid, eh.orderdate, RANK(orderdate) w FROM order_data eh
window w as (partition by cmscustid order by orderdate);
The rank function instead returns the rank of the order date over all all
order dates.
Example snippet from above
Actual :
6758783 27APR2012 94
6758783 23JUN2012 95
6758785 14DEC2012 96
6758795 18DEC2011 97
6758796 06MAY2012 98
6758798 24MAR2013 99
6758799 23NOV2012 100
Expected :
6758783 27APR2012 1
6758783 23JUN2012 2
6758785 14DEC2012 1
6758795 18DEC2011 1
6758796 06MAY2012 1
6758798 24MAR2013 1
6758799 23NOV2012 1
-b
On Wed, Jul 24, 2013 at 3:17 PM, Shahar Glixman <sglix...@outbrain.com>wrote:
> the argument to rank is simply some value, whereas the rank function
> compare this value
> to the previous value received, if value is same, rank returns ++index,
> otherwise, rank return 1.
> pseudo code:
>
> class Rank {
> int index;
> Object previousValue = null;
> int evaluate(Object value) {
> if (value == previousValue) {
> return ++index;
> }
> previousValue = value;
> index = 1;
> return 1;
> }
>
>
> On Wed, Jul 24, 2013 at 9:59 PM, j.barrett Strausser <
> j.barrett.straus...@gmail.com> wrote:
>
>> It seems as though I am required to pass in an argument to RANK().
>>
>> What is the effect of passing this argument in ?
>>
>> In a RANK function the output for RANK should be the number of rows
>> preceding
>> a row in a given window. As windows are specified by the partition and
>> order by fields I don't understand the effect of passing in an arg to RANK
>>
>> Are the other non-aggregate function similar? Meaning : Cume_dist, Ntile
>> --
>>
>>
>> https://github.com/bearrito
>> @deepbearrito
>>
>
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