From bb45c640411af61279bea044f8d108f9da96b735 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Wed, 6 Nov 2013 13:26:30 -0500 Subject: Support default arguments and named-argument notation for window functions. These things didn't work because the planner omitted to do the necessary preprocessing of a WindowFunc's argument list. Add the few dozen lines of code needed to handle that. Although this sounds like a feature addition, it's really a bug fix because the default-argument case was likely to crash previously, due to lack of checking of the number of supplied arguments in the built-in window functions. It's not a security issue because there's no way for a non-superuser to create a window function definition with defaults that refers to a built-in C function, but nonetheless people might be annoyed that it crashes rather than producing a useful error message. So back-patch as far as the patch applies easily, which turns out to be 9.2. I'll put a band-aid in earlier versions as a separate patch. (Note that these features still don't work for aggregates, and fixing that case will be harder since we represent aggregate arg lists as target lists not bare expression lists. There's no crash risk though because CREATE AGGREGATE doesn't accept defaults, and we reject named-argument notation when parsing an aggregate call.) --- src/backend/utils/adt/ruleutils.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'src/backend/utils/adt/ruleutils.c') diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c index 04b1c4f8956..915fb7a6689 100644 --- a/src/backend/utils/adt/ruleutils.c +++ b/src/backend/utils/adt/ruleutils.c @@ -7461,6 +7461,7 @@ get_windowfunc_expr(WindowFunc *wfunc, deparse_context *context) StringInfo buf = context->buf; Oid argtypes[FUNC_MAX_ARGS]; int nargs; + List *argnames; ListCell *l; if (list_length(wfunc->args) > FUNC_MAX_ARGS) @@ -7468,18 +7469,20 @@ get_windowfunc_expr(WindowFunc *wfunc, deparse_context *context) (errcode(ERRCODE_TOO_MANY_ARGUMENTS), errmsg("too many arguments"))); nargs = 0; + argnames = NIL; foreach(l, wfunc->args) { Node *arg = (Node *) lfirst(l); - Assert(!IsA(arg, NamedArgExpr)); + if (IsA(arg, NamedArgExpr)) + argnames = lappend(argnames, ((NamedArgExpr *) arg)->name); argtypes[nargs] = exprType(arg); nargs++; } appendStringInfo(buf, "%s(", generate_function_name(wfunc->winfnoid, nargs, - NIL, argtypes, + argnames, argtypes, false, NULL)); /* winstar can be set only in zero-argument aggregates */ if (wfunc->winstar) -- cgit v1.2.3