On Wed, Dec 13, 2017 at 12:55 PM, Rushabh Lathia
wrote:
> HI,
>
> Consider the below test:
>
> postgres@110311=#call sum(2+2);
> 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.
>
> Call stack:
>
> (gdb) bt
> #0 0x7fef9b5851d7 in raise () from /lib64/libc.so.6
> #1 0x7fef9b5868c8 in abort () from /lib64/libc.so.6
> #2 0x009ec5b5 in ExceptionalCondition (conditionName=0xb7e12b
> "!(((bool) 0))", errorType=0xb7e04c "FailedAssertion",
> fileName=0xb7e040 "parse_agg.c", lineNumber=349) at assert.c:54
> #3 0x005dc3b6 in check_agglevels_and_constraints (pstate=0x2d1ba90,
> expr=0x2d1bd80) at parse_agg.c:349
> #4 0x005dc104 in transformAggregateCall (pstate=0x2d1ba90,
> agg=0x2d1bd80, args=0x2d1c3c0, aggorder=0x0, agg_distinct=0 '\000') at
> parse_agg.c:237
> #5 0x005f4df7 in ParseFuncOrColumn (pstate=0x2d1ba90,
> funcname=0x2d10578, fargs=0x2d1c3c0, last_srf=0x0, fn=0x2d10760, proc_call=1
> '\001',
> location=5) at parse_func.c:726
>
>
> Here it's hitting Assert() because pstate->p_expr_kind is set
> to EXPR_KIND_NONE for the CallStmt function resolution.
>
I think it shouldn't reach this code. Like a normal function
invocation, an aggregate invocation should not be allowed in a CALL
statement. Here's patch to fix it. I thought that window function
invocations and casts had similar problem, but they are prohibited by
backend grammar.
--
Best Wishes,
Ashutosh Bapat
EnterpriseDB Corporation
The Postgres Database Company
diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c
index 2f20516..5ba6065 100644
--- a/src/backend/parser/parse_func.c
+++ b/src/backend/parser/parse_func.c
@@ -336,6 +336,16 @@ ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
Form_pg_aggregate classForm;
int catDirectArgs;
+ if (proc_call)
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_FUNCTION),
+ errmsg("%s is not a procedure",
+ func_signature_string(funcname, nargs,
+ argnames,
+ actual_arg_types)),
+ errhint("To call an aggregate function, use SELECT."),
+ parser_errposition(pstate, location)));
+
tup = SearchSysCache1(AGGFNOID, ObjectIdGetDatum(funcid));
if (!HeapTupleIsValid(tup)) /* should not happen */
elog(ERROR, "cache lookup failed for aggregate %u", funcid);
