Re: Internal error XX000 with enable_partition_pruning=on, pg 11beta1 on Debian

On 16 July 2018 at 06:55, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Also, in the Plan
> representation, I'd suggest avoiding situations where a data structure
> is sometimes a List of Lists of PartitionedRelPruneInfo and sometimes
> just a single-level List.  Saving one ListCell isn't worth the code
> complexity and error-proneness of that.

Thinking about this some more, I don't quite see any reason that the
partitioned_rels for a single hierarchy couldn't just be a Bitmapset
instead of an IntList.

A parent partition is always going to have a lower relid than its
children, so that means that the top level parent will just have the
lowest member in the set.

There's already code in the inheritance_planner which rebuilds the
IntList from a Bitmapset:

while ((i = bms_next_member(partitioned_relids, i)) >= 0)
   partitioned_rels = lappend_int(partitioned_rels, i);

ExecLockNonLeafAppendTables could be made to accept a Bitmapset rather
than a List. In fact, we could probably get rid of the nested loops if
we did it that way.

What do you think?

-- 
 David Rowley                   http://www.2ndQuadrant.com/
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