Hi There,
Can anyone please tell me is there any Rank function available in datastage.
or is there any way to achieve this?
thanks
Rank
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Because you can't do rank until all rows have been processed. That's why it's not an ETL function. ETL is best performed as a stream of data.
A second reason is that there is no one standard for the handling of tied ranks. Nonparametric statistics text books devote many pages to alternative strategies that you can use.
There is nothing whatsoever to stop you from either writing your own stage or developing a technique for ranks with stage variables in a Transformer stage, but you have to make some decisions first, both about handling of tied ranks and of the format of output. And, of course, you need to process the data twice (even if the first is only sorting).
A second reason is that there is no one standard for the handling of tied ranks. Nonparametric statistics text books devote many pages to alternative strategies that you can use.
There is nothing whatsoever to stop you from either writing your own stage or developing a technique for ranks with stage variables in a Transformer stage, but you have to make some decisions first, both about handling of tied ranks and of the format of output. And, of course, you need to process the data twice (even if the first is only sorting).
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Of course you can, and I said so. But there's nothing out of the box - either you write your own stage (probably a Build stage) or you use stage variables in a Transformer stage (bearing in mind all I've already said about handling tied ranks) to process sorted data.
One of the difficulties of not having premium membership is that you can't read everything I write.
One of the difficulties of not having premium membership is that you can't read everything I write.
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That's not something that's under my control but, as I understand it, that price was purely an introductory offer and won't be repeated. The current price is still less than 30c per day.
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Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.
Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.