#0  0x0000702b3328857f in raise () from /lib64/libc.so.6
#1  0x0000702b33272895 in abort () from /lib64/libc.so.6
#2  0x0000000000a59a9d in ExceptionalCondition (conditionName=0xc52e84 "!(0)", errorType=0xc51f96 "FailedAssertion", fileName=0xc51fe6 "createplan.c", lineNumber=5937) at assert.c:54
#3  0x00000000007d4ab5 in prepare_sort_from_pathkeys (lefttree=0x2bbbce0, pathkeys=0x2b7a130, relids=0x0, reqColIdx=0x0, adjust_tlist_in_place=false, p_numsortkeys=0x7ffe1abcfd6c, p_sortColIdx=0x7ffe1abcfd60, p_sortOperators=0x7ffe1abcfd58, p_collations=0x7ffe1abcfd50, 
    p_nullsFirst=0x7ffe1abcfd48) at createplan.c:5937
#4  0x00000000007d4e7f in make_incrementalsort_from_pathkeys (lefttree=0x2bbbce0, pathkeys=0x2b7a130, relids=0x0, presortedCols=1) at createplan.c:6101
#5  0x00000000007cdd3f in create_incrementalsort_plan (root=0x2b787c0, best_path=0x2bb92b0, flags=1) at createplan.c:2019
#6  0x00000000007cb7ad in create_plan_recurse (root=0x2b787c0, best_path=0x2bb92b0, flags=1) at createplan.c:469
#7  0x00000000007cd778 in create_gather_merge_plan (root=0x2b787c0, best_path=0x2bb94a0) at createplan.c:1764
#8  0x00000000007cb8fb in create_plan_recurse (root=0x2b787c0, best_path=0x2bb94a0, flags=4) at createplan.c:516
#9  0x00000000007cdf10 in create_agg_plan (root=0x2b787c0, best_path=0x2bb9b28) at createplan.c:2115
#10 0x00000000007cb834 in create_plan_recurse (root=0x2b787c0, best_path=0x2bb9b28, flags=3) at createplan.c:484
#11 0x00000000007cdc16 in create_sort_plan (root=0x2b787c0, best_path=0x2bba1e8, flags=1) at createplan.c:1986
#12 0x00000000007cb78e in create_plan_recurse (root=0x2b787c0, best_path=0x2bba1e8, flags=1) at createplan.c:464
#13 0x00000000007cb4ae in create_plan (root=0x2b787c0, best_path=0x2bba1e8) at createplan.c:330
#14 0x00000000007db63c in standard_planner (parse=0x2bf5bc8, cursorOptions=256, boundParams=0x0) at planner.c:413
#15 0x00000000007db3b4 in planner (parse=0x2bf5bc8, cursorOptions=256, boundParams=0x0) at planner.c:275
#16 0x00000000008e404f in pg_plan_query (querytree=0x2bf5bc8, cursorOptions=256, boundParams=0x0) at postgres.c:878
#17 0x0000000000657afa in ExplainOneQuery (query=0x2bf5bc8, cursorOptions=256, into=0x0, es=0x2bf5fc0, queryString=0x2a74be8 "EXPLAIN (COSTS OFF)\nSELECT a, sum(b), count(*) FROM pagg_tab_ml GROUP BY a HAVING avg(b) < 3 ORDER BY 1, 2, 3;", params=0x0, queryEnv=0x0) at explain.c:371
#18 0x0000000000657804 in ExplainQuery (pstate=0x2a95ff8, stmt=0x2a76628, queryString=0x2a74be8 "EXPLAIN (COSTS OFF)\nSELECT a, sum(b), count(*) FROM pagg_tab_ml GROUP BY a HAVING avg(b) < 3 ORDER BY 1, 2, 3;", params=0x0, queryEnv=0x0, dest=0x2a95f60) at explain.c:259
#19 0x00000000008ec75e in standard_ProcessUtility (pstmt=0x2b8a050, queryString=0x2a74be8 "EXPLAIN (COSTS OFF)\nSELECT a, sum(b), count(*) FROM pagg_tab_ml GROUP BY a HAVING avg(b) < 3 ORDER BY 1, 2, 3;", context=PROCESS_UTILITY_TOPLEVEL, params=0x0, queryEnv=0x0, dest=0x2a95f60, 
    completionTag=0x7ffe1abd0430 "") at utility.c:675
#20 0x00000000008ebfbe in ProcessUtility (pstmt=0x2b8a050, queryString=0x2a74be8 "EXPLAIN (COSTS OFF)\nSELECT a, sum(b), count(*) FROM pagg_tab_ml GROUP BY a HAVING avg(b) < 3 ORDER BY 1, 2, 3;", context=PROCESS_UTILITY_TOPLEVEL, params=0x0, queryEnv=0x0, dest=0x2a95f60, 
    completionTag=0x7ffe1abd0430 "") at utility.c:360
#21 0x00000000008eafab in PortalRunUtility (portal=0x2adc558, pstmt=0x2b8a050, isTopLevel=true, setHoldSnapshot=true, dest=0x2a95f60, completionTag=0x7ffe1abd0430 "") at pquery.c:1175
#22 0x00000000008eacb2 in FillPortalStore (portal=0x2adc558, isTopLevel=true) at pquery.c:1035
#23 0x00000000008ea60e in PortalRun (portal=0x2adc558, count=9223372036854775807, isTopLevel=true, run_once=true, dest=0x2b8a148, altdest=0x2b8a148, completionTag=0x7ffe1abd0620 "") at pquery.c:765
#24 0x00000000008e45be in exec_simple_query (query_string=0x2a74be8 "EXPLAIN (COSTS OFF)\nSELECT a, sum(b), count(*) FROM pagg_tab_ml GROUP BY a HAVING avg(b) < 3 ORDER BY 1, 2, 3;") at postgres.c:1215
#25 0x00000000008e8912 in PostgresMain (argc=1, argv=0x2aa07c0, dbname=0x2aa0530 "regression", username=0x2a707e8 "user") at postgres.c:4249
#26 0x000000000083ed83 in BackendRun (port=0x2a99c50) at postmaster.c:4431
#27 0x000000000083e551 in BackendStartup (port=0x2a99c50) at postmaster.c:4122
#28 0x000000000083a977 in ServerLoop () at postmaster.c:1704
#29 0x000000000083a223 in PostmasterMain (argc=8, argv=0x2a6e670) at postmaster.c:1377
#30 0x000000000075a823 in main (argc=8, argv=0x2a6e670) at main.c:228