[CF 5478] v20 - SQL/JSON json_table PLAN clause

This branch was automatically generated by a robot using patches from an
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https://commitfest.postgresql.org/patch/5478

The branch will be overwritten each time a new patch version is posted to
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on the master branch.

Patch(es): https://www.postgresql.org/message-id/CAN-LCVPSYfLZHcmvct-_nGZ7peTat-Bo--04K9VXGU8p_TcbWg@mail.gmail.com
Author(s): Fedor Sigaev, Alexander Korotkov, Andrew Dunstan, Amit Langote, Nikita Glukhov, Oleg Bartunov, Anton Melnikov, Nikita Malakhov

Author: Commitfest Bot

src/backend/nodes/makefuncs.c

@@ -963,6 +963,60 @@ makeJsonBehavior(JsonBehaviorType btype, Node *expr, int location)
 	return behavior;
 }
 
+/*
+ * makeJsonTableDefaultPlan -
+ *	   creates a JsonTablePlanSpec node to represent a "default" JSON_TABLE plan
+ *	   with given join strategy
+ */
+Node *
+makeJsonTableDefaultPlan(JsonTablePlanJoinType join_type, int location)
+{
+	JsonTablePlanSpec *n = makeNode(JsonTablePlanSpec);
+
+	n->plan_type = JSTP_DEFAULT;
+	n->join_type = join_type;
+	n->location = location;
+
+	return (Node *) n;
+}
+
+/*
+ * makeJsonTableSimplePlan -
+ *	   creates a JsonTablePlanSpec node to represent a "simple" JSON_TABLE plan
+ *	   for given PATH
+ */
+Node *
+makeJsonTableSimplePlan(char *pathname, int location)
+{
+	JsonTablePlanSpec *n = makeNode(JsonTablePlanSpec);
+
+	n->plan_type = JSTP_SIMPLE;
+	n->pathname = pathname;
+	n->location = location;
+
+	return (Node *) n;
+}
+
+/*
+ * makeJsonTableJoinedPlan -
+ *	   creates a JsonTablePlanSpec node to represent join between the given
+ *	   pair of plans
+ */
+Node *
+makeJsonTableJoinedPlan(JsonTablePlanJoinType type, Node *plan1, Node *plan2,
+						int location)
+{
+	JsonTablePlanSpec *n = makeNode(JsonTablePlanSpec);
+
+	n->plan_type = JSTP_JOINED;
+	n->join_type = type;
+	n->plan1 = castNode(JsonTablePlanSpec, plan1);
+	n->plan2 = castNode(JsonTablePlanSpec, plan2);
+	n->location = location;
+
+	return (Node *) n;
+}
+
 /*
  * makeJsonKeyValue -
  *	  creates a JsonKeyValue node

src/backend/parser/gram.y

@@ -656,6 +656,14 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 				json_table
 				json_table_column_definition
 				json_table_column_path_clause_opt
+				json_table_plan_clause_opt
+				json_table_plan
+				json_table_plan_simple
+				json_table_plan_outer
+				json_table_plan_inner
+				json_table_plan_union
+				json_table_plan_cross
+				json_table_plan_primary
 %type <list>	json_name_and_value_list
 				json_value_expr_list
 				json_array_aggregate_order_by_clause_opt
@@ -667,6 +675,9 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 %type <ival>	json_behavior_type
 				json_predicate_type_constraint
 				json_quotes_clause_opt
+				json_table_default_plan_choices
+				json_table_default_plan_inner_outer
+				json_table_default_plan_union_cross
 				json_wrapper_behavior
 %type <boolean>	json_key_uniqueness_constraint_opt
 				json_object_constructor_null_clause_opt
@@ -14315,6 +14326,7 @@ json_table:
 				json_value_expr ',' a_expr json_table_path_name_opt
 				json_passing_clause_opt
 				COLUMNS '(' json_table_column_definition_list ')'
+				json_table_plan_clause_opt
 				json_on_error_clause_opt
 			')'
 				{
@@ -14326,13 +14338,15 @@ json_table:
 						castNode(A_Const, $5)->val.node.type != T_String)
 						ereport(ERROR,
 								errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-								errmsg("only string constants are supported in JSON_TABLE path specification"),
+								errmsg("only string constants are supported in"
+									   " JSON_TABLE path specification"),
 								parser_errposition(@5));
 					pathstring = castNode(A_Const, $5)->val.sval.sval;
 					n->pathspec = makeJsonTablePathSpec(pathstring, $6, @5, @6);
 					n->passing = $7;
 					n->columns = $10;
-					n->on_error = (JsonBehavior *) $12;
+					n->planspec = (JsonTablePlanSpec *) $12;
+					n->on_error = (JsonBehavior *) $13;
 					n->location = @1;
 					$$ = (Node *) n;
 				}
@@ -14424,8 +14438,7 @@ json_table_column_definition:
 					JsonTableColumn *n = makeNode(JsonTableColumn);
 
 					n->coltype = JTC_NESTED;
-					n->pathspec = (JsonTablePathSpec *)
-						makeJsonTablePathSpec($3, NULL, @3, -1);
+					n->pathspec = makeJsonTablePathSpec($3, NULL, @3, -1);
 					n->columns = $6;
 					n->location = @1;
 					$$ = (Node *) n;
@@ -14436,8 +14449,7 @@ json_table_column_definition:
 					JsonTableColumn *n = makeNode(JsonTableColumn);
 
 					n->coltype = JTC_NESTED;
-					n->pathspec = (JsonTablePathSpec *)
-						makeJsonTablePathSpec($3, $5, @3, @5);
+					n->pathspec = makeJsonTablePathSpec($3, $5, @3, @5);
 					n->columns = $8;
 					n->location = @1;
 					$$ = (Node *) n;
@@ -14456,6 +14468,83 @@ json_table_column_path_clause_opt:
 				{ $$ = NULL; }
 		;
 
+json_table_plan_clause_opt:
+			PLAN '(' json_table_plan ')'
+				{ $$ = $3; }
+			| PLAN DEFAULT '(' json_table_default_plan_choices ')'
+				{ $$ = makeJsonTableDefaultPlan($4, @1); }
+			| /* EMPTY */
+				{ $$ = NULL; }
+		;
+
+json_table_plan:
+			json_table_plan_simple
+			| json_table_plan_outer
+			| json_table_plan_inner
+			| json_table_plan_union
+			| json_table_plan_cross
+		;
+
+json_table_plan_simple:
+			name
+				{ $$ = makeJsonTableSimplePlan($1, @1); }
+		;
+
+json_table_plan_outer:
+			json_table_plan_simple OUTER_P json_table_plan_primary
+				{ $$ = makeJsonTableJoinedPlan(JSTP_JOIN_OUTER, $1, $3, @1); }
+		;
+
+json_table_plan_inner:
+			json_table_plan_simple INNER_P json_table_plan_primary
+				{ $$ = makeJsonTableJoinedPlan(JSTP_JOIN_INNER, $1, $3, @1); }
+		;
+
+json_table_plan_union:
+			json_table_plan_primary UNION json_table_plan_primary
+				{ $$ = makeJsonTableJoinedPlan(JSTP_JOIN_UNION, $1, $3, @1); }
+			| json_table_plan_union UNION json_table_plan_primary
+				{ $$ = makeJsonTableJoinedPlan(JSTP_JOIN_UNION, $1, $3, @1); }
+		;
+
+json_table_plan_cross:
+			json_table_plan_primary CROSS json_table_plan_primary
+				{ $$ = makeJsonTableJoinedPlan(JSTP_JOIN_CROSS, $1, $3, @1); }
+			| json_table_plan_cross CROSS json_table_plan_primary
+				{ $$ = makeJsonTableJoinedPlan(JSTP_JOIN_CROSS, $1, $3, @1); }
+		;
+
+json_table_plan_primary:
+			json_table_plan_simple
+				{ $$ = $1; }
+			| '(' json_table_plan ')'
+				{
+					castNode(JsonTablePlanSpec, $2)->location = @1;
+					$$ = $2;
+				}
+		;
+
+json_table_default_plan_choices:
+			json_table_default_plan_inner_outer
+				{ $$ = $1 | JSTP_JOIN_UNION; }
+			| json_table_default_plan_union_cross
+				{ $$ = $1 | JSTP_JOIN_OUTER; }
+			| json_table_default_plan_inner_outer ',' json_table_default_plan_union_cross
+				{ $$ = $1 | $3; }
+			| json_table_default_plan_union_cross ',' json_table_default_plan_inner_outer
+				{ $$ = $1 | $3; }
+		;
+
+json_table_default_plan_inner_outer:
+			INNER_P						{ $$ = JSTP_JOIN_INNER; }
+			| OUTER_P					{ $$ = JSTP_JOIN_OUTER; }
+		;
+
+json_table_default_plan_union_cross:
+			UNION						{ $$ = JSTP_JOIN_UNION; }
+			| CROSS						{ $$ = JSTP_JOIN_CROSS; }
+		;
+
 /*****************************************************************************
  *
  *	Type syntax