Hi, I am able to hit "ERROR: cache lookup failed for function %d" while I am dropping function from another session.
*Reproducible steps are as(I tried on current head d8a75b1308b133502ae3):* *Step 1) Fire below query from session-1 to create a function:* create function fun1(int) returns record as ' DECLARE retval RECORD; BEGIN SELECT INTO retval 5, 10, 15; RETURN retval; END;' language plpgsql; *Step 2)* Attach PID of session-1 into gdb and set a breakpoint into internal_get_result_type and then press c. (gdb) b internal_get_result_type Breakpoint 1 at 0x5565dd4f3ce4: file funcapi.c, line 325. (gdb) c Continuing. *Step 3)* Fire below select command from session-1: SELECT * FROM fun1(1500) AS (a int, b int, c int); *Step 3) Open session-2 and drop the function:* psql (15devel) Type "help" for help. postgres=# drop function fun1; DROP FUNCTION postgres=# *Step 4)* Press 'c' in gdb for 2 times and we will get an error in the 1st session. (gdb) c Continuing. Breakpoint 1, internal_get_result_type (funcid=16384, call_expr=0x5565de885af0, rsinfo=0x0, resultTypeId=0x7ffc94572608, resultTupleDesc=0x7ffc94572628) at funcapi.c:325 (gdb) c Continuing. postgres=# SELECT * FROM fun1(1500) AS (a int, b int, c int); ERROR: cache lookup failed for function 16384 *Call stack of error:* > Breakpoint 2, errfinish (filename=0x55e0b8907c6f "funcapi.c", lineno=336, > funcname=0x55e0b89083a0 <__func__.23015> "internal_get_result_type") at > elog.c:515 > 515 ErrorData *edata = &errordata[errordata_stack_depth]; > (gdb) bt > #0 errfinish (filename=0x55e0b8907c6f "funcapi.c", lineno=336, > funcname=0x55e0b89083a0 <__func__.23015> "internal_get_result_type") at > elog.c:515 > #1 0x000055e0b86abdaf in internal_get_result_type (funcid=16384, > call_expr=0x55e0ba9e2ad0, rsinfo=0x0, resultTypeId=0x7ffcb7ca4918, > resultTupleDesc=0x7ffcb7ca4938) > at funcapi.c:336 > #2 0x000055e0b86ab6d0 in get_expr_result_type (expr=0x55e0ba9e2ad0, > resultTypeId=0x7ffcb7ca4918, resultTupleDesc=0x7ffcb7ca4938) at > funcapi.c:230 > #3 0x000055e0b7fef027 in ExecInitFunctionScan (node=0x55e0ba9e3cd0, > estate=0x55e0ba9d2fe0, eflags=16) at nodeFunctionscan.c:370 > #4 0x000055e0b7fbb408 in ExecInitNode (node=0x55e0ba9e3cd0, > estate=0x55e0ba9d2fe0, eflags=16) at execProcnode.c:254 > #5 0x000055e0b7faa1d5 in InitPlan (queryDesc=0x55e0ba926f50, eflags=16) > at execMain.c:936 > #6 0x000055e0b7fa84b6 in standard_ExecutorStart > (queryDesc=0x55e0ba926f50, eflags=16) at execMain.c:263 > #7 0x000055e0b7fa7fc7 in ExecutorStart (queryDesc=0x55e0ba926f50, > eflags=0) at execMain.c:143 > #8 0x000055e0b83ba8de in PortalStart (portal=0x55e0ba968870, params=0x0, > eflags=0, snapshot=0x0) at pquery.c:512 > #9 0x000055e0b83ae112 in exec_simple_query (query_string=0x55e0ba906760 > "SELECT * FROM fun1(1500) AS (a int, b int, c int);") at postgres.c:1175 > #10 0x000055e0b83b7a86 in PostgresMain (argc=1, argv=0x7ffcb7ca4f70, > dbname=0x55e0ba932770 "postgres", username=0x55e0ba932748 "mahendrathalor") > at postgres.c:4488 > #11 0x000055e0b825161b in BackendRun (port=0x55e0ba929730) at > postmaster.c:4519 > #12 0x000055e0b8250971 in BackendStartup (port=0x55e0ba929730) at > postmaster.c:4241 > #13 0x000055e0b8248a1b in ServerLoop () at postmaster.c:1758 > #14 0x000055e0b8247c18 in PostmasterMain (argc=3, argv=0x55e0ba8fee70) at > postmaster.c:1430 > #15 0x000055e0b808dbe9 in main (argc=3, argv=0x55e0ba8fee70) at main.c:199 > cache lookup failed errors are never an expected behavior(Thanks Robert Hass for your opinion) so I think we should fix this error. I haven't debugged it so I will debug it and will post my findings in the coming days. -- Thanks and Regards Mahendra Singh Thalor EnterpriseDB: http://www.enterprisedb.com
