There's no good reason for using two different keywords for filtering and it harms composability. But of course SQL isn't very composable anyhow.
Preferably, SQL would look more like:
FROM Foo f
WHERE f.value < 10
JOIN Bar b on b.id = f.bar_id
WHERE b.other_value > 20
SELECT f.group, f.value
GROUP BY f.group the_group AGGREGATING SUM(f.value) the_sum
WHERE the_sum > 100
ORDER BY the_group
This is pretty close to how my Julia library [0] for composable construction of SQL queries works:
From(foo) |>
Where(Get.value .< 10) |>
Join(From(bar) |> As(:bar), on = Get.bar.id .== Get.bar_id) |>
Where(Get.bar.other_value .> 20) |>
Select(Get.group, Get.value) |>
Group(Get.group) |>
Where(Agg.sum(Get.value) .> 100) |>
Order(Get.group)
Let me know any feedback — as you can see it's still at the proposal stage. If it gains some traction I'll write an implementation.