Re: New Window Function: ROW_NUMBER_DESC() OVER() ?
| От | David G. Johnston |
|---|---|
| Тема | Re: New Window Function: ROW_NUMBER_DESC() OVER() ? |
| Дата | |
| Msg-id | CAKFQuwaGhHJTsAR4k0Q_fdnerA-DkRw1HruqyW2W_6wGA+W2Gw@mail.gmail.com обсуждение исходный текст |
| Ответ на | RE: New Window Function: ROW_NUMBER_DESC() OVER() ? (Maiquel Grassi <grassi@hotmail.com.br>) |
| Ответы |
RE: New Window Function: ROW_NUMBER_DESC() OVER() ?
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| Список | pgsql-hackers |
On Tuesday, January 16, 2024, Maiquel Grassi <grassi@hotmail.com.br> wrote:
Hello David, how are you?
Firstly, I apologize if I wasn't clear in what I intended to propose. I used a very specific example here, and it wasn't very clear what I really wanted to bring up for discussion.I understand that it's possible to order the "returned dataset" using "order by ... desc."
It is, but it is also possible to order a window frame/partition by specifying order by in the over clause. Which is what I showed, and what you should try to use. That orders the enumeration, you can still order, or not, the output dataset.
I don't have a base column to use for "order by," and I also can't use CTID column.
Then you really don’t have an ordering in the data itself. This is unusual and not really worth adding a new function to deal with.
How can I do this without using my reversed enumeration "row_number desc" function?
Count() over() - row_number() over()
Please don’t top-post replies, in-line and trim like I’m doing.
David J.
P.s. if you really don’t care about logical order you probably should just let your front-end deal with it.
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