Re: remaining sql/json patches

Hi Alexander,

On Fri, Apr 5, 2024 at 3:00 PM Alexander Lakhin <exclusion(at)gmail(dot)com> wrote:
>
> Hello Amit,
>
> 04.04.2024 15:02, Amit Langote wrote:
> > Pushed after fixing these and a few other issues. I didn't include
> > the testing function you proposed in your other email. It sounds
> > useful for testing locally but will need some work before we can
> > include it in the tree.
> >
> > I'll post the rebased 0002 tomorrow after addressing your comments.
>
> Please look at an assertion failure:
> TRAP: failed Assert("count <= tupdesc->natts"), File: "parse_relation.c", Line: 3048, PID: 1325146
>
> triggered by the following query:
> SELECT * FROM JSON_TABLE('0', '$' COLUMNS (js int PATH '$')),
> COALESCE(row(1)) AS (a int, b int);
>
> Without JSON_TABLE() I get:
> ERROR: function return row and query-specified return row do not match
> DETAIL: Returned row contains 1 attribute, but query expects 2.

Thanks for the report.

Seems like it might be a pre-existing issue, because I can also
reproduce the crash with:

SELECT * FROM COALESCE(row(1)) AS (a int, b int);
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.
!>

Backtrace:

#0 __pthread_kill_implementation (threadid=281472845250592,
signo=signo(at)entry=6, no_tid=no_tid(at)entry=0) at pthread_kill.c:44
#1 0x0000ffff806c4334 in __pthread_kill_internal (signo=6,
threadid=<optimized out>) at pthread_kill.c:78
#2 0x0000ffff8067c73c in __GI_raise (sig=sig(at)entry=6) at
../sysdeps/posix/raise.c:26
#3 0x0000ffff80669034 in __GI_abort () at abort.c:79
#4 0x0000000000ad9d4c in ExceptionalCondition (conditionName=0xcbb368
"!(tupdesc->natts >= colcount)", errorType=0xcbb278 "FailedAssertion",
fileName=0xcbb2c8 "nodeFunctionscan.c",
lineNumber=379) at assert.c:54
#5 0x000000000073edec in ExecInitFunctionScan (node=0x293d4ed0,
estate=0x293d51b8, eflags=16) at nodeFunctionscan.c:379
#6 0x0000000000724bc4 in ExecInitNode (node=0x293d4ed0,
estate=0x293d51b8, eflags=16) at execProcnode.c:248
#7 0x000000000071b1cc in InitPlan (queryDesc=0x292f5d78, eflags=16)
at execMain.c:1006
#8 0x0000000000719f6c in standard_ExecutorStart
(queryDesc=0x292f5d78, eflags=16) at execMain.c:252
#9 0x0000000000719cac in ExecutorStart (queryDesc=0x292f5d78,
eflags=0) at execMain.c:134
#10 0x0000000000945520 in PortalStart (portal=0x29399458, params=0x0,
eflags=0, snapshot=0x0) at pquery.c:527
#11 0x000000000093ee50 in exec_simple_query (query_string=0x29332d38
"SELECT * FROM COALESCE(row(1)) AS (a int, b int);") at
postgres.c:1175
#12 0x0000000000943cb8 in PostgresMain (argc=1, argv=0x2935d610,
dbname=0x2935d450 "postgres", username=0x2935d430 "amit") at
postgres.c:4297
#13 0x000000000087e978 in BackendRun (port=0x29356c00) at postmaster.c:4517
#14 0x000000000087e0bc in BackendStartup (port=0x29356c00) at postmaster.c:4200
#15 0x0000000000879638 in ServerLoop () at postmaster.c:1725
#16 0x0000000000878eb4 in PostmasterMain (argc=3, argv=0x292eeac0) at
postmaster.c:1398
#17 0x0000000000791db8 in main (argc=3, argv=0x292eeac0) at main.c:228

Backtrace looks a bit different with a query similar to yours:

SELECT * FROM generate_series(1, 1), COALESCE(row(1)) AS (a int, b int);
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.
!>

#0 __pthread_kill_implementation (threadid=281472845250592,
signo=signo(at)entry=6, no_tid=no_tid(at)entry=0) at pthread_kill.c:44
#1 0x0000ffff806c4334 in __pthread_kill_internal (signo=6,
threadid=<optimized out>) at pthread_kill.c:78
#2 0x0000ffff8067c73c in __GI_raise (sig=sig(at)entry=6) at
../sysdeps/posix/raise.c:26
#3 0x0000ffff80669034 in __GI_abort () at abort.c:79
#4 0x0000000000ad9d4c in ExceptionalCondition (conditionName=0xc903b0
"!(count <= tupdesc->natts)", errorType=0xc8f8c8 "FailedAssertion",
fileName=0xc8f918 "parse_relation.c",
lineNumber=2649) at assert.c:54
#5 0x0000000000649664 in expandTupleDesc (tupdesc=0x293da188,
eref=0x293d7318, count=2, offset=0, rtindex=2, sublevels_up=0,
location=-1, include_dropped=true, colnames=0x0,
colvars=0xffffc39253c8) at parse_relation.c:2649
#6 0x0000000000648d08 in expandRTE (rte=0x293d7390, rtindex=2,
sublevels_up=0, location=-1, include_dropped=true, colnames=0x0,
colvars=0xffffc39253c8) at parse_relation.c:2361
#7 0x0000000000849bd0 in build_physical_tlist (root=0x293d5318,
rel=0x293d88e8) at plancat.c:1681
#8 0x0000000000806ad0 in create_scan_plan (root=0x293d5318,
best_path=0x293cd888, flags=0) at createplan.c:605
#9 0x000000000080666c in create_plan_recurse (root=0x293d5318,
best_path=0x293cd888, flags=0) at createplan.c:389
#10 0x000000000080c4e8 in create_nestloop_plan (root=0x293d5318,
best_path=0x293d96f0) at createplan.c:4056
#11 0x0000000000807464 in create_join_plan (root=0x293d5318,
best_path=0x293d96f0) at createplan.c:1037
#12 0x0000000000806680 in create_plan_recurse (root=0x293d5318,
best_path=0x293d96f0, flags=1) at createplan.c:394
#13 0x000000000080658c in create_plan (root=0x293d5318,
best_path=0x293d96f0) at createplan.c:326
#14 0x0000000000816534 in standard_planner (parse=0x293d3728,
cursorOptions=256, boundParams=0x0) at planner.c:413
#15 0x00000000008162b4 in planner (parse=0x293d3728,
cursorOptions=256, boundParams=0x0) at planner.c:275
#16 0x000000000093e984 in pg_plan_query (querytree=0x293d3728,
cursorOptions=256, boundParams=0x0) at postgres.c:877
#17 0x000000000093eb04 in pg_plan_queries (querytrees=0x293d8018,
cursorOptions=256, boundParams=0x0) at postgres.c:967
#18 0x000000000093edc4 in exec_simple_query (query_string=0x29332d38
"SELECT * FROM generate_series(1, 1), COALESCE(row(1)) AS (a int, b
int);") at postgres.c:1142
#19 0x0000000000943cb8 in PostgresMain (argc=1, argv=0x2935d4f8,
dbname=0x2935d338 "postgres", username=0x2935d318 "amit") at
postgres.c:4297
#20 0x000000000087e978 in BackendRun (port=0x29356dd0) at postmaster.c:4517
#21 0x000000000087e0bc in BackendStartup (port=0x29356dd0) at postmaster.c:4200
#22 0x0000000000879638 in ServerLoop () at postmaster.c:1725
#23 0x0000000000878eb4 in PostmasterMain (argc=3, argv=0x292eeac0) at
postmaster.c:1398
#24 0x0000000000791db8 in main (argc=3, argv=0x292eeac0) at main.c:228

I suspect the underlying issue is the same, though I haven't figured
out what it is, except a guess that addRangeTableEntryForFunction()
might be missing something to handle this sanely.

Reproducible down to v12.

--
Thanks, Amit Langote