Simon Riggs wrote:
The planner already uses the Append node to put together multiple plans.
The great thing is it will put together IndexScans and SeqScans as
applicable. No need for multi-scans as a special node type.

Yes... only that mixing 'concurrent' index scans in the right order would probably save us an extra sort step in some cases. Consider this with hash partitioning on (id):

  SELECT * FROM test WHERE id > 1 AND id < 9999999 ORDER BY id;

Every partition should have an index on (id), so we already have pretty well sorted data, we just need to mix the results of the index scan in the correct order, no?



---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
      choose an index scan if your joining column's datatypes do not

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