Re: Window ?

On Wed, Jun 13, 2018 at 7:33 AM, Olivier Leprêtre <[email protected]>
wrote:

>
> I want to convert records into lines,
>
>
>
> 1        att1    att2    att3    att4
>
> 2        att5    att6    ...
>
>
>
​I would recommend either an actual array (array_agg function) or a
structured string (string_agg function)

SELECT road, array_agg(colA ORDER BY seg)
FROM tbl
GROUP BY road;

Otherwise you will need a output 31 columns with unused columns holding
null.  You can do that brute-force or you can leverage the tablefunc
extension's crosstab function.

https://www.postgresql.org/docs/10/static/tablefunc.html

David J.
​