| Project [id#0L, a#0, b#0, index#0L] | |
| +- Project [id#0L, a#0, b#0, distributed_sequence_id#0L AS index#0L] | |
| +- AttachDistributedSequence[distributed_sequence_id#0L, id#0L, a#0, b#0] Index: distributed_sequence_id#0L | |
| +- LocalRelation <empty>, [id#0L, a#0, b#0] |