I wrote: > OK, so here's a finished set of patches for this issue. > 0001 is the same patch I posted on Tuesday; I kept it separate just > because it seemed like a largely separable set of changes. (Note that > the undesirable regression test output changes are undone by 0002.) > 0002 implements the map-vars-back-to-the-inheritance parent change > per my sketch. Notice that relation aliases and Var names change > underneath Appends/MergeAppends, but Vars above one are (mostly) > printed the same as before. On the whole I think this is a good > set of test output changes, reflecting a more predictable approach > to assigning aliases to inheritance children. But somebody else > might see it differently I suppose. > Finally, 0003 is the remaining portion of David's patch to allow > deletion of all of an Append/MergeAppend's sub-plans during > executor startup pruning.
I pushed these, and the buildfarm immediately got a bad case of the measles. All the members using force_parallel_mode = regress fail on the new regression test case added by 0003, with diffs like this: diff -U3 /home/pgbf/buildroot/HEAD/pgsql.build/src/test/regress/expected/partition_prune.out /home/pgbf/buildroot/HEAD/pgsql.build/src/test/regress/results/partition_prune.out --- /home/pgbf/buildroot/HEAD/pgsql.build/src/test/regress/expected/partition_prune.out Thu Dec 12 00:40:04 2019 +++ /home/pgbf/buildroot/HEAD/pgsql.build/src/test/regress/results/partition_prune.out Thu Dec 12 00:45:44 2019 @@ -3169,10 +3169,12 @@ -------------------------------------------- Limit (actual rows=0 loops=1) Output: ma_test.a, ma_test.b + Worker 0: actual rows=0 loops=1 -> Merge Append (actual rows=0 loops=1) Sort Key: ma_test.b + Worker 0: actual rows=0 loops=1 Subplans Removed: 3 -(5 rows) +(7 rows) deallocate mt_q2; reset plan_cache_mode; This looks to me like there's some other part of EXPLAIN that needs to be updated for the possibility of zero child nodes, but I didn't find out just where in a few minutes of searching. As a stopgap to get back to green buildfarm, I removed this specific test case, but we need to look at it closer. regards, tom lane