This undoes my hurried commit
776a2c887, restoring the removed test case
in a form that passes with or without force_parallel_mode = regress.
It turns out that force_parallel_mode = regress simply fails to mask
the Worker lines that will be produced by EXPLAIN (ANALYZE, VERBOSE).
I'd say that's a bug in that feature, as its entire alleged reason
for existence is to make the EXPLAIN output the same. It's certainly
not a bug in the plan node pruning logic. Fortunately, this test case
doesn't really need to use ANALYZE, so just drop that.
Discussion: https://postgr.es/m/18891.
1576109690@sss.pgh.pa.us
(0 rows)
deallocate mt_q1;
+prepare mt_q2 (int) as select * from ma_test where a >= $1 order by b limit 1;
+-- Ensure output list looks sane when the MergeAppend has no subplans.
+explain (verbose, costs off) execute mt_q2 (35);
+ QUERY PLAN
+--------------------------------
+ Limit
+ Output: ma_test.a, ma_test.b
+ -> Merge Append
+ Sort Key: ma_test.b
+ Subplans Removed: 3
+(5 rows)
+
+deallocate mt_q2;
-- ensure initplan params properly prune partitions
explain (analyze, costs off, summary off, timing off) select * from ma_test where a >= (select min(b) from ma_test_p2) order by b;
QUERY PLAN
deallocate mt_q1;
+prepare mt_q2 (int) as select * from ma_test where a >= $1 order by b limit 1;
+
+-- Ensure output list looks sane when the MergeAppend has no subplans.
+explain (verbose, costs off) execute mt_q2 (35);
+
+deallocate mt_q2;
+
-- ensure initplan params properly prune partitions
explain (analyze, costs off, summary off, timing off) select * from ma_test where a >= (select min(b) from ma_test_p2) order by b;