Re: rolling window without aggregation

Huang, Suya wrote
> Hi SQL experts,
>
> I've got a question here, is that possible to implement a window function
> without aggregation? Any SQL could get below desired result?
>
> For example:
>
> Table input
> date | id
> ------------+--------
> 2014-04-26 | A
> 2014-05-03 | B
> 2014-05-10 | C
> 2014-05-17 | D
> 2014-05-24 | E
> 2014-05-31 | F
>
> Expected output, use 2 week roll up as an example:
> date | id
> ------------+--------
> 2014-04-26 | A
> 2014-05-03 | A
> 2014-05-03 | B
> 2014-05-10 | B
> 2014-05-10 | C
> 2014-05-17 | C
> 2014-05-17 | D
> 2014-05-24 | D
> 2014-05-24 | E
> 2014-05-31 | E
> 2014-05-31 | F
>
>
>
> Thanks,
> Suya

Use the lead() function to create a second column. Then write a UNION ALL
query to covert the two columns into one.

David J.

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