Ecto.Query.WindowAPI.nth_value
You're seeing just the function
nth_value
, go back to Ecto.Query.WindowAPI module for more information.
Returns value evaluated at the row that is the nth row of the window
frame (counting from 1); nil
if no such row.
from p in Post,
select: nth_value(p.id, 4) |> over(partition_by: p.category_id, order_by: p.date)
Note that this function must be invoked using window function syntax.