[erlang-questions] Ordered set with lower_bound

[Max Lapshin]

> If by "frame number N" you mean "the Nth object in the ordered set"
> then you can use ets:slot for this
>
> Colm

No,no, I was not too clear: I store milliseconds as id of frame and
need something like following expression:

seek(Time) ->
  "SELECT id FROM frames WHERE is_keyframe = 't' AND timestamp <= Time
ORDER BY id DESC limit 1"

Something like this. Binary tree will be ideal.