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From Shahar Glixman <sglix...@outbrain.com>
Subject Re: Semantics of Rank.
Date Wed, 24 Jul 2013 19:17:58 GMT
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.strausser@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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