Support CTE/JOIN usage for PIVOT operator

src/backend/executor/execSRF.c

@@ -25,6 +25,7 @@
 #include "funcapi.h"
 #include "miscadmin.h"
 #include "nodes/nodeFuncs.h"
+#include "parser/parser.h"
 #include "parser/parse_coerce.h"
 #include "pgstat.h"
 #include "utils/acl.h"
@@ -33,6 +34,8 @@
 #include "utils/memutils.h"
 #include "utils/typcache.h"
 
+/* Hook to set TSQL pivot data to fcinfo */
+pass_pivot_data_to_fcinfo_hook_type pass_pivot_data_to_fcinfo_hook = NULL;
 
 /* static function decls */
 static void init_sexpr(Oid foid, Oid input_collation, Expr *node,
@@ -202,7 +205,12 @@ ExecMakeTableFunctionResult(SetExprState *setexpr,
 		/* Treat setexpr as a generic expression */
 		InitFunctionCallInfoData(*fcinfo, NULL, 0, InvalidOid, NULL, NULL);
 	}
-
+
+	if (sql_dialect == SQL_DIALECT_TSQL && pass_pivot_data_to_fcinfo_hook)
+	{
+		(pass_pivot_data_to_fcinfo_hook)(fcinfo, setexpr->expr);
+	}
+
 	/*
 	 * Switch to short-lived context for calling the function or expression.
 	 */

src/backend/nodes/makefuncs.c

@@ -534,6 +534,7 @@ makeFuncExpr(Oid funcid, Oid rettype, List *args,
 	funcexpr->inputcollid = inputcollid;
 	funcexpr->args = args;
 	funcexpr->location = -1;
+	funcexpr->context = NULL;
 
 	return funcexpr;
 }
@@ -600,6 +601,7 @@ makeFuncCall(List *name, List *args, CoercionForm funcformat, int location)
 	n->func_variadic = false;
 	n->funcformat = funcformat;
 	n->location = location;
+	n->context = NULL;
 	return n;
 }
 

src/backend/optimizer/util/clauses.c

@@ -2601,6 +2601,7 @@ eval_const_expressions_mutator(Node *node,
 				newexpr->inputcollid = expr->inputcollid;
 				newexpr->args = args;
 				newexpr->location = expr->location;
+				newexpr->context = expr->context;
 				return (Node *) newexpr;
 			}
 		case T_OpExpr:
@@ -4562,6 +4563,7 @@ evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
 	newexpr->inputcollid = input_collid;
 	newexpr->args = args;
 	newexpr->location = -1;
+	newexpr->context = NULL;
 
 	return evaluate_expr((Expr *) newexpr, result_type, result_typmod,
 						 result_collid);
@@ -4674,6 +4676,7 @@ inline_function(Oid funcid, Oid result_type, Oid result_collid,
 	fexpr->inputcollid = input_collid;
 	fexpr->args = args;
 	fexpr->location = -1;
+	fexpr->context = NULL;
 
 	/* Fetch the function body */
 	tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);

src/backend/parser/analyze.c

@@ -89,7 +89,7 @@ pre_transform_setop_tree_hook_type pre_transform_setop_tree_hook = NULL;
 /* Hook to reset a query's targetlist after modification in pre_transfrom_sort_clause */
 pre_transform_setop_sort_clause_hook_type pre_transform_setop_sort_clause_hook = NULL;
 
-/* Hooks for transform TSQL pivot clause in select stmt */
+/* Hook to transform TSQL pivot clause in select stmt */
 transform_pivot_clause_hook_type transform_pivot_clause_hook = NULL;
 
 static Query *transformOptionalSelectInto(ParseState *pstate, Node *parseTree);

src/backend/parser/parse_func.c

@@ -765,6 +765,10 @@ ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
 		/* funccollid and inputcollid will be set by parse_collate.c */
 		funcexpr->args = fargs;
 		funcexpr->location = location;
+		funcexpr->context = NULL;
+
+		if (fn != NULL)
+			funcexpr->context = copyObject(fn->context);
 
 		retval = (Node *) funcexpr;
 	}

src/include/executor/executor.h

@@ -473,6 +473,8 @@ extern Datum ExecMakeFunctionResultSet(SetExprState *fcache,
 									   MemoryContext argContext,
 									   bool *isNull,
 									   ExprDoneCond *isDone);
+typedef void (*pass_pivot_data_to_fcinfo_hook_type)(FunctionCallInfo fcinfo, Expr *expr);
+extern PGDLLEXPORT pass_pivot_data_to_fcinfo_hook_type pass_pivot_data_to_fcinfo_hook;
 
 /*
  * prototypes from functions in execScan.c

src/include/nodes/parsenodes.h

@@ -432,6 +432,7 @@ typedef struct FuncCall
 	bool		func_variadic;	/* last argument was labeled VARIADIC */
 	CoercionForm funcformat;	/* how to display this node */
 	int			location;		/* token location, or -1 if unknown */
+	Node 	   *context;		/* pass necessary info through planner and executor */
 } FuncCall;
 
 /*

src/include/nodes/primnodes.h

@@ -695,6 +695,8 @@ typedef struct FuncExpr
 	List	   *args;
 	/* token location, or -1 if unknown */
 	int			location;
+	/* pass necessary info through planner and executor */
+	Node 	   *context pg_node_attr(query_jumble_ignore, read_write_ignore, read_as(NULL));
 } FuncExpr;
 
 /*