From ff58d54ca52d87a2594793c7a904fa9982c95374 Mon Sep 17 00:00:00 2001
From: Andy Fan <zhihui.fan1213@gmail.com>
Date: Thu, 14 Sep 2023 16:58:13 +0800
Subject: [PATCH v14 1/2] optimize casting jsonb to a given type.

Previously after we get a JsonbValue, we need to convert it to
Jsonb first then cast the Jsonb to the given type. In this patch,
we covert the JsonbValue to the desired type directly.
---
 src/backend/utils/adt/jsonb.c         | 152 ++++++++++++++++++++++++++
 src/backend/utils/adt/jsonbsubs.c     |   4 +-
 src/backend/utils/adt/jsonfuncs.c     | 125 ++++++++++++++-------
 src/backend/utils/adt/jsonpath_exec.c |  31 ++++--
 src/include/catalog/catversion.h      |   3 +-
 src/include/catalog/pg_proc.dat       |  46 ++++++--
 src/include/utils/jsonb.h             |  11 +-
 src/test/regress/expected/jsonb.out   | 112 ++++++++++++++++++-
 src/test/regress/sql/jsonb.sql        |  66 ++++++++++-
 9 files changed, 485 insertions(+), 65 deletions(-)

diff --git a/src/backend/utils/adt/jsonb.c b/src/backend/utils/adt/jsonb.c
index 9781852b0cb..e2efb28a685 100644
--- a/src/backend/utils/adt/jsonb.c
+++ b/src/backend/utils/adt/jsonb.c
@@ -17,11 +17,15 @@
 #include "catalog/pg_proc.h"
 #include "catalog/pg_type.h"
 #include "funcapi.h"
+#include "nodes/makefuncs.h"
+#include "nodes/supportnodes.h"
+#include "parser/parse_coerce.h"
 #include "libpq/pqformat.h"
 #include "miscadmin.h"
 #include "utils/builtins.h"
 #include "utils/date.h"
 #include "utils/datetime.h"
+#include "utils/fmgroids.h"
 #include "utils/json.h"
 #include "utils/jsonb.h"
 #include "utils/jsonfuncs.h"
@@ -2038,6 +2042,154 @@ cannotCastJsonbValue(enum jbvType type, const char *sqltype)
 	elog(ERROR, "unknown jsonb type: %d", (int) type);
 }
 
+
+/*
+ * jsonb_cast_support()
+ *
+ * Planner support function for casting a jsonb extraction to a numeric
+ * or bool data type. Instead of converting a jsonbvalue to jsonb, the new
+ * method will cast the jsonbvalue to the desired data type directly.
+ */
+Datum
+jsonb_cast_support(PG_FUNCTION_ARGS)
+{
+	Node	   *rawreq = (Node *) PG_GETARG_POINTER(0);
+
+	if (IsA(rawreq, SupportRequestSimplify))
+	{
+		SupportRequestSimplify *req = (SupportRequestSimplify *) rawreq;
+		FuncExpr	*fexpr = req->fcall;
+		FuncExpr	*jsonb_start_func = NULL, *jsonb_finish_func = NULL, *final_func = NULL;
+		Node		*input;
+		Oid			new_func_id = InvalidOid;
+		List		*args;
+		Oid			input_func_id, collid, inputcollid;
+		bool		retset = false,  variadic = false;
+
+		Assert(list_length(fexpr->args) == 1);
+		input = (Node *) linitial(fexpr->args);
+
+		if (IsA(input, OpExpr))
+		{
+			OpExpr	*opExpr = castNode(OpExpr, input);
+			input_func_id = opExpr->opfuncid;
+			collid = opExpr->opcollid;
+			inputcollid = opExpr->inputcollid;
+			args = opExpr->args;
+		}
+		else if (IsA(input, FuncExpr))
+		{
+			FuncExpr *funcExpr = castNode(FuncExpr, input);
+			input_func_id = funcExpr->funcid;
+			collid = funcExpr->funccollid;
+			inputcollid = funcExpr->inputcollid;
+			args = funcExpr->args;
+		}
+		else
+			/* not the desired pattern. */
+			PG_RETURN_POINTER(NULL);
+
+
+		switch (input_func_id)
+		{
+			case F_JSONB_OBJECT_FIELD:
+				new_func_id = F_JSONB_OBJECT_FIELD_START;
+				break;
+			case F_JSONB_ARRAY_ELEMENT:
+				new_func_id = F_JSONB_ARRAY_ELEMENT_START;
+				break;
+			case F_JSONB_EXTRACT_PATH:
+				new_func_id = F_JSONB_EXTRACT_PATH_START;
+				variadic = true;
+				break;
+			case F_JSONB_PATH_QUERY:
+				new_func_id = F_JSONB_PATH_QUERY_START;
+				retset = true;
+				break;
+			case F_JSONB_PATH_QUERY_FIRST:
+				new_func_id = F_JSONB_PATH_QUERY_FIRST_START;
+				break;
+			default:
+				new_func_id = InvalidOid;
+				break;
+		}
+
+		if (!OidIsValid(new_func_id))
+			PG_RETURN_POINTER(NULL);
+
+		jsonb_start_func = makeFuncExpr(new_func_id, INTERNALOID, args,
+										collid, inputcollid,
+										COERCE_EXPLICIT_CALL);
+		jsonb_start_func->funcretset = retset;
+		jsonb_start_func->funcvariadic = variadic;
+
+		/* relabel the first arguments as 'internal'. */
+		linitial(jsonb_start_func->args) = makeRelabelType(linitial(jsonb_start_func->args),
+														   INTERNALOID, -1,
+														   InvalidOid,
+														   COERCE_IMPLICIT_CAST);
+		switch (fexpr->funcresulttype)
+		{
+			case INT2OID:
+			case INT4OID:
+			case INT8OID:
+			case FLOAT4OID:
+			case FLOAT8OID:
+			case NUMERICOID:
+				jsonb_finish_func = makeFuncExpr(F_JSONB_FINISH_NUMERIC, NUMERICOID,
+												 list_make2(jsonb_start_func,
+															makeConst(OIDOID,
+																	  -1,
+																	  InvalidOid,
+																	  sizeof(Oid),
+																	  ObjectIdGetDatum(fexpr->funcresulttype),
+																	  false,
+																	  true)),
+												 collid, inputcollid, COERCE_EXPLICIT_CALL);
+
+				if (fexpr->funcresulttype != NUMERICOID)
+				{
+					final_func = (FuncExpr *)coerce_type(NULL, (Node *)jsonb_finish_func, NUMERICOID,
+														 fexpr->funcresulttype, 0, COERCION_EXPLICIT,
+														 COERCE_EXPLICIT_CAST, fexpr->location);
+				}
+				else
+					final_func = jsonb_finish_func;
+
+				PG_RETURN_POINTER(final_func);
+			case BOOLOID:
+				final_func = makeFuncExpr(F_JSONB_FINISH_BOOL, BOOLOID,
+										  list_make1(jsonb_start_func), collid,
+										  inputcollid, COERCE_EXPLICIT_CALL);
+				PG_RETURN_POINTER(final_func);
+			default:
+				PG_RETURN_POINTER(NULL);
+		}
+	}
+
+	PG_RETURN_POINTER(NULL);
+}
+
+
+Datum
+jsonb_finish_numeric(PG_FUNCTION_ARGS)
+{
+	JsonbValue	*v = (JsonbValue *)PG_GETARG_POINTER(0);
+	Oid			final_oid = PG_GETARG_OID(1);
+	if (v->type != jbvNumeric)
+		cannotCastJsonbValue(v->type, format_type_be(final_oid));
+	PG_RETURN_NUMERIC(v->val.numeric);
+}
+
+Datum
+jsonb_finish_bool(PG_FUNCTION_ARGS)
+{
+	JsonbValue	*v = (JsonbValue *)PG_GETARG_POINTER(0);
+	if (v->type != jbvBool)
+		cannotCastJsonbValue(v->type, "boolean");
+	PG_RETURN_BOOL(v->val.boolean);
+}
+
 Datum
 jsonb_bool(PG_FUNCTION_ARGS)
 {
diff --git a/src/backend/utils/adt/jsonbsubs.c b/src/backend/utils/adt/jsonbsubs.c
index de0ae3604ff..cb050c65ef7 100644
--- a/src/backend/utils/adt/jsonbsubs.c
+++ b/src/backend/utils/adt/jsonbsubs.c
@@ -251,7 +251,7 @@ jsonb_subscript_fetch(ExprState *state,
 									  workspace->index,
 									  sbsrefstate->numupper,
 									  op->resnull,
-									  false);
+									  JsonbValue_AsJsonb);
 }
 
 /*
@@ -343,7 +343,7 @@ jsonb_subscript_fetch_old(ExprState *state,
 												   sbsrefstate->upperindex,
 												   sbsrefstate->numupper,
 												   &sbsrefstate->prevnull,
-												   false);
+												   JsonbValue_AsJsonb);
 	}
 }
 
diff --git a/src/backend/utils/adt/jsonfuncs.c b/src/backend/utils/adt/jsonfuncs.c
index a4bfa5e4040..eded8e4f32b 100644
--- a/src/backend/utils/adt/jsonfuncs.c
+++ b/src/backend/utils/adt/jsonfuncs.c
@@ -357,7 +357,7 @@ static JsonParseErrorType get_scalar(void *state, char *token, JsonTokenType tok
 static Datum get_path_all(FunctionCallInfo fcinfo, bool as_text);
 static text *get_worker(text *json, char **tpath, int *ipath, int npath,
 						bool normalize_results);
-static Datum get_jsonb_path_all(FunctionCallInfo fcinfo, bool as_text);
+static Datum get_jsonb_path_all(FunctionCallInfo fcinfo, JsonbValueTarget target);
 static text *JsonbValueAsText(JsonbValue *v);
 
 /* semantic action functions for json_array_length */
@@ -492,6 +492,20 @@ static JsonParseErrorType transform_string_values_object_field_start(void *state
 static JsonParseErrorType transform_string_values_array_element_start(void *state, bool isnull);
 static JsonParseErrorType transform_string_values_scalar(void *state, char *token, JsonTokenType tokentype);
 
+Datum
+jsonbvalue_covert(JsonbValue *jbv, JsonbValueTarget target)
+{
+	switch (target)
+	{
+		case JsonbValue_AsJsonbValue:
+			PG_RETURN_POINTER(jbv);
+		case JsonbValue_AsJsonb:
+			PG_RETURN_JSONB_P(JsonbValueToJsonb(jbv));
+		case JsonbValue_AsText:
+			PG_RETURN_TEXT_P(JsonbValueAsText(jbv));
+	}
+	PG_RETURN_POINTER(NULL);
+}
 
 /*
  * pg_parse_json_or_errsave
@@ -848,13 +862,12 @@ json_object_field(PG_FUNCTION_ARGS)
 		PG_RETURN_NULL();
 }
 
-Datum
-jsonb_object_field(PG_FUNCTION_ARGS)
+static Datum
+jsonb_object_field_internal(FunctionCallInfo fcinfo, JsonbValueTarget target)
 {
 	Jsonb	   *jb = PG_GETARG_JSONB_P(0);
 	text	   *key = PG_GETARG_TEXT_PP(1);
 	JsonbValue *v;
-	JsonbValue	vbuf;
 
 	if (!JB_ROOT_IS_OBJECT(jb))
 		PG_RETURN_NULL();
@@ -862,12 +875,23 @@ jsonb_object_field(PG_FUNCTION_ARGS)
 	v = getKeyJsonValueFromContainer(&jb->root,
 									 VARDATA_ANY(key),
 									 VARSIZE_ANY_EXHDR(key),
-									 &vbuf);
+									 NULL);
+	if (v == NULL)
+		PG_RETURN_NULL();
 
-	if (v != NULL)
-		PG_RETURN_JSONB_P(JsonbValueToJsonb(v));
+	return jsonbvalue_covert(v, target);
+}
 
-	PG_RETURN_NULL();
+Datum
+jsonb_object_field(PG_FUNCTION_ARGS)
+{
+	return jsonb_object_field_internal(fcinfo, JsonbValue_AsJsonb);
+}
+
+Datum
+jsonb_object_field_start(PG_FUNCTION_ARGS)
+{
+	return jsonb_object_field_internal(fcinfo, JsonbValue_AsJsonbValue);
 }
 
 Datum
@@ -923,8 +947,8 @@ json_array_element(PG_FUNCTION_ARGS)
 		PG_RETURN_NULL();
 }
 
-Datum
-jsonb_array_element(PG_FUNCTION_ARGS)
+static Datum
+jsonb_array_element_internal(FunctionCallInfo fcinfo, JsonbValueTarget target)
 {
 	Jsonb	   *jb = PG_GETARG_JSONB_P(0);
 	int			element = PG_GETARG_INT32(1);
@@ -945,10 +969,22 @@ jsonb_array_element(PG_FUNCTION_ARGS)
 	}
 
 	v = getIthJsonbValueFromContainer(&jb->root, element);
-	if (v != NULL)
-		PG_RETURN_JSONB_P(JsonbValueToJsonb(v));
+	if (v == NULL)
+		PG_RETURN_NULL();
 
-	PG_RETURN_NULL();
+	return jsonbvalue_covert(v, target);
+}
+
+Datum
+jsonb_array_element(PG_FUNCTION_ARGS)
+{
+	return jsonb_array_element_internal(fcinfo, JsonbValue_AsJsonb);
+}
+
+Datum
+jsonb_array_element_start(PG_FUNCTION_ARGS)
+{
+	return jsonb_array_element_internal(fcinfo, JsonbValue_AsJsonbValue);
 }
 
 Datum
@@ -1476,17 +1512,23 @@ get_scalar(void *state, char *token, JsonTokenType tokentype)
 Datum
 jsonb_extract_path(PG_FUNCTION_ARGS)
 {
-	return get_jsonb_path_all(fcinfo, false);
+	return get_jsonb_path_all(fcinfo, JsonbValue_AsJsonb);
 }
 
 Datum
 jsonb_extract_path_text(PG_FUNCTION_ARGS)
 {
-	return get_jsonb_path_all(fcinfo, true);
+	return get_jsonb_path_all(fcinfo, JsonbValue_AsText);
+}
+
+Datum
+jsonb_extract_path_start(PG_FUNCTION_ARGS)
+{
+	return get_jsonb_path_all(fcinfo, JsonbValue_AsJsonbValue);
 }
 
 static Datum
-get_jsonb_path_all(FunctionCallInfo fcinfo, bool as_text)
+get_jsonb_path_all(FunctionCallInfo fcinfo, JsonbValueTarget target)
 {
 	Jsonb	   *jb = PG_GETARG_JSONB_P(0);
 	ArrayType  *path = PG_GETARG_ARRAYTYPE_P(1);
@@ -1508,7 +1550,7 @@ get_jsonb_path_all(FunctionCallInfo fcinfo, bool as_text)
 
 	deconstruct_array_builtin(path, TEXTOID, &pathtext, &pathnulls, &npath);
 
-	res = jsonb_get_element(jb, pathtext, npath, &isnull, as_text);
+	res = jsonb_get_element(jb, pathtext, npath, &isnull, target);
 
 	if (isnull)
 		PG_RETURN_NULL();
@@ -1517,7 +1559,7 @@ get_jsonb_path_all(FunctionCallInfo fcinfo, bool as_text)
 }
 
 Datum
-jsonb_get_element(Jsonb *jb, Datum *path, int npath, bool *isnull, bool as_text)
+jsonb_get_element(Jsonb *jb, Datum *path, int npath, bool *isnull, JsonbValueTarget target)
 {
 	JsonbContainer *container = &jb->root;
 	JsonbValue *jbvp = NULL;
@@ -1550,16 +1592,26 @@ jsonb_get_element(Jsonb *jb, Datum *path, int npath, bool *isnull, bool as_text)
 	 */
 	if (npath <= 0 && jbvp == NULL)
 	{
-		if (as_text)
-		{
-			return PointerGetDatum(cstring_to_text(JsonbToCString(NULL,
-																  container,
-																  VARSIZE(jb))));
-		}
-		else
+		switch(target)
 		{
-			/* not text mode - just hand back the jsonb */
-			PG_RETURN_JSONB_P(jb);
+			case JsonbValue_AsText:
+				return PointerGetDatum(cstring_to_text(JsonbToCString(NULL,
+																	  container,
+																	  VARSIZE(jb))));
+			case JsonbValue_AsJsonb:
+				/* just hand back the jsonb */
+				PG_RETURN_JSONB_P(jb);
+			case JsonbValue_AsJsonbValue:
+				{
+					/* just hand back the jsonb */
+					JsonbValue *jbv = NULL;
+					if (JB_ROOT_IS_ARRAY(jb) && JB_ROOT_IS_SCALAR(jb))
+						PG_RETURN_POINTER(getIthJsonbValueFromContainer(container, 0));
+
+					jbv = palloc0(sizeof(JsonbValue));
+					JsonbToJsonbValue(jb, jbv);
+					PG_RETURN_POINTER(jbv);
+				}
 		}
 	}
 
@@ -1645,23 +1697,14 @@ jsonb_get_element(Jsonb *jb, Datum *path, int npath, bool *isnull, bool as_text)
 		}
 	}
 
-	if (as_text)
-	{
-		if (jbvp->type == jbvNull)
-		{
-			*isnull = true;
-			return PointerGetDatum(NULL);
-		}
 
-		return PointerGetDatum(JsonbValueAsText(jbvp));
-	}
-	else
+	if (target == JsonbValue_AsText && jbvp->type == jbvNull)
 	{
-		Jsonb	   *res = JsonbValueToJsonb(jbvp);
-
-		/* not text mode - just hand back the jsonb */
-		PG_RETURN_JSONB_P(res);
+		*isnull = true;
+		return PointerGetDatum(NULL);
 	}
+
+	return jsonbvalue_covert(jbvp, target);
 }
 
 Datum
diff --git a/src/backend/utils/adt/jsonpath_exec.c b/src/backend/utils/adt/jsonpath_exec.c
index 2d0599b4aaa..5eef14f93ed 100644
--- a/src/backend/utils/adt/jsonpath_exec.c
+++ b/src/backend/utils/adt/jsonpath_exec.c
@@ -393,7 +393,7 @@ jsonb_path_match_opr(PG_FUNCTION_ARGS)
  *		rowset.
  */
 static Datum
-jsonb_path_query_internal(FunctionCallInfo fcinfo, bool tz)
+jsonb_path_query_internal(FunctionCallInfo fcinfo, bool tz, JsonbValueTarget target)
 {
 	FuncCallContext *funcctx;
 	List	   *found;
@@ -435,19 +435,25 @@ jsonb_path_query_internal(FunctionCallInfo fcinfo, bool tz)
 	v = lfirst(c);
 	funcctx->user_fctx = list_delete_first(found);
 
-	SRF_RETURN_NEXT(funcctx, JsonbPGetDatum(JsonbValueToJsonb(v)));
+	SRF_RETURN_NEXT(funcctx, jsonbvalue_covert(v, target));
 }
 
 Datum
 jsonb_path_query(PG_FUNCTION_ARGS)
 {
-	return jsonb_path_query_internal(fcinfo, false);
+	return jsonb_path_query_internal(fcinfo, false, JsonbValue_AsJsonb);
 }
 
 Datum
 jsonb_path_query_tz(PG_FUNCTION_ARGS)
 {
-	return jsonb_path_query_internal(fcinfo, true);
+	return jsonb_path_query_internal(fcinfo, true, JsonbValue_AsJsonb);
+}
+
+Datum
+jsonb_path_query_start(PG_FUNCTION_ARGS)
+{
+	return jsonb_path_query_internal(fcinfo, false, JsonbValue_AsJsonbValue);
 }
 
 /*
@@ -487,7 +493,7 @@ jsonb_path_query_array_tz(PG_FUNCTION_ARGS)
  *		item.  If there are no items, NULL returned.
  */
 static Datum
-jsonb_path_query_first_internal(FunctionCallInfo fcinfo, bool tz)
+jsonb_path_query_first_internal(FunctionCallInfo fcinfo, bool tz, JsonbValueTarget target)
 {
 	Jsonb	   *jb = PG_GETARG_JSONB_P(0);
 	JsonPath   *jp = PG_GETARG_JSONPATH_P(1);
@@ -498,7 +504,10 @@ jsonb_path_query_first_internal(FunctionCallInfo fcinfo, bool tz)
 	(void) executeJsonPath(jp, vars, jb, !silent, &found, tz);
 
 	if (JsonValueListLength(&found) >= 1)
-		PG_RETURN_JSONB_P(JsonbValueToJsonb(JsonValueListHead(&found)));
+	{
+		JsonbValue *jbv = JsonValueListHead(&found);
+		return jsonbvalue_covert(jbv, target);
+	}
 	else
 		PG_RETURN_NULL();
 }
@@ -506,13 +515,19 @@ jsonb_path_query_first_internal(FunctionCallInfo fcinfo, bool tz)
 Datum
 jsonb_path_query_first(PG_FUNCTION_ARGS)
 {
-	return jsonb_path_query_first_internal(fcinfo, false);
+	return jsonb_path_query_first_internal(fcinfo, false, JsonbValue_AsJsonb);
 }
 
 Datum
 jsonb_path_query_first_tz(PG_FUNCTION_ARGS)
 {
-	return jsonb_path_query_first_internal(fcinfo, true);
+	return jsonb_path_query_first_internal(fcinfo, true, JsonbValue_AsJsonb);
+}
+
+Datum
+jsonb_path_query_first_start(PG_FUNCTION_ARGS)
+{
+	return jsonb_path_query_first_internal(fcinfo, false, JsonbValue_AsJsonbValue);
 }
 
 /********************Execute functions for JsonPath**************************/
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index ab9a7ac1f79..fb83a7a29df 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -57,6 +57,5 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	202308251
-
+#define CATALOG_VERSION_NO	202309151
 #endif
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 9805bc61180..ef719aac6bb 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -4587,25 +4587,25 @@
   proname => 'pg_lsn', prorettype => 'pg_lsn', proargtypes => 'numeric',
   prosrc => 'numeric_pg_lsn' },
 
-{ oid => '3556', descr => 'convert jsonb to boolean',
+{ oid => '3556', descr => 'convert jsonb to boolean', prosupport => 'jsonb_cast_support',
   proname => 'bool', prorettype => 'bool', proargtypes => 'jsonb',
   prosrc => 'jsonb_bool' },
 { oid => '3449', descr => 'convert jsonb to numeric',
-  proname => 'numeric', prorettype => 'numeric', proargtypes => 'jsonb',
+  proname => 'numeric', prorettype => 'numeric', proargtypes => 'jsonb', prosupport => 'jsonb_cast_support',
   prosrc => 'jsonb_numeric' },
-{ oid => '3450', descr => 'convert jsonb to int2',
+{ oid => '3450', descr => 'convert jsonb to int2', prosupport => 'jsonb_cast_support',
   proname => 'int2', prorettype => 'int2', proargtypes => 'jsonb',
   prosrc => 'jsonb_int2' },
-{ oid => '3451', descr => 'convert jsonb to int4',
+{ oid => '3451', descr => 'convert jsonb to int4', prosupport => 'jsonb_cast_support',
   proname => 'int4', prorettype => 'int4', proargtypes => 'jsonb',
   prosrc => 'jsonb_int4' },
-{ oid => '3452', descr => 'convert jsonb to int8',
+{ oid => '3452', descr => 'convert jsonb to int8', prosupport => 'jsonb_cast_support',
   proname => 'int8', prorettype => 'int8', proargtypes => 'jsonb',
   prosrc => 'jsonb_int8' },
-{ oid => '3453', descr => 'convert jsonb to float4',
+{ oid => '3453', descr => 'convert jsonb to float4', prosupport => 'jsonb_cast_support',
   proname => 'float4', prorettype => 'float4', proargtypes => 'jsonb',
   prosrc => 'jsonb_float4' },
-{ oid => '2580', descr => 'convert jsonb to float8',
+{ oid => '2580', descr => 'convert jsonb to float8', prosupport => 'jsonb_cast_support',
   proname => 'float8', prorettype => 'float8', proargtypes => 'jsonb',
   prosrc => 'jsonb_float8' },
 
@@ -9947,6 +9947,30 @@
   proname => 'jsonb_object_field_text', prorettype => 'text',
   proargtypes => 'jsonb text', proargnames => '{from_json, field_name}',
   prosrc => 'jsonb_object_field_text' },
+{ oid => '4552', descr => 'extract jsonbvalue from jsonb for the given field',
+  proname => 'jsonb_object_field_start', prorettype => 'internal',
+  proargtypes => 'internal text', proargnames => '{from_json, field_name}',
+  prosrc => 'jsonb_object_field_start' },
+{ oid => '3813', descr => 'extract josnbvalue from jsonb array for the given index',
+  proname => 'jsonb_array_element_start', prorettype => 'internal',
+  proargtypes => 'internal int4', proargnames => '{from_jsonb, element_index}',
+  prosrc => 'jsonb_array_element_start' },
+{ oid => '4549', descr => 'extract jsonbvalue from jsonb for the given paths',
+  proname => 'jsonb_extract_path_start', provariadic => 'text', prorettype => 'internal',
+  proargtypes => 'internal _text', proallargtypes => '{internal,_text}',
+  proargmodes => '{i,v}', proargnames => '{from_jsonb,path_elems}',
+  prosrc => 'jsonb_extract_path_start'},
+{ oid => '4553', descr => 'convert a jsonbvalue to numeric',
+  proname => 'jsonb_finish_numeric', prorettype => 'numeric',
+  proargtypes => 'internal oid', proargnames => '{from_jsonvalue,target_oid}',
+  prosrc => 'jsonb_finish_numeric' },
+{ oid => '4554', descr => 'convert a jsonbvalue to boolean',
+  proname => 'jsonb_finish_bool', prorettype => 'bool',
+  proargtypes => 'internal', proargnames => '{jsonvalue}',
+  prosrc => 'jsonb_finish_bool' },
+{ oid => '3814', descr => 'planner support for numeric(jsonb)',
+  proname => 'jsonb_cast_support', prorettype => 'internal',
+  proargtypes => 'internal', prosrc => 'jsonb_cast_support' },
 { oid => '3215',
   proname => 'jsonb_array_element', prorettype => 'jsonb',
   proargtypes => 'jsonb int4', proargnames => '{from_json, element_index}',
@@ -10139,6 +10163,10 @@
   proname => 'jsonb_path_query', prorows => '1000', proretset => 't',
   prorettype => 'jsonb', proargtypes => 'jsonb jsonpath jsonb bool',
   prosrc => 'jsonb_path_query' },
+{ oid => '4557', descr => 'jsonpath query as jsonbvalue',
+  proname => 'jsonb_path_query_start', prorows => '1000', proretset => 't',
+  prorettype => 'internal', proargtypes => 'internal jsonpath jsonb bool',
+  prosrc => 'jsonb_path_query_start' },
 { oid => '4007', descr => 'jsonpath query wrapped into array',
   proname => 'jsonb_path_query_array', prorettype => 'jsonb',
   proargtypes => 'jsonb jsonpath jsonb bool',
@@ -10147,6 +10175,10 @@
   proname => 'jsonb_path_query_first', prorettype => 'jsonb',
   proargtypes => 'jsonb jsonpath jsonb bool',
   prosrc => 'jsonb_path_query_first' },
+{ oid => '4555', descr => 'jsonpath query first item as jsonbvalue',
+  proname => 'jsonb_path_query_first_start', prorettype => 'internal',
+  proargtypes => 'internal jsonpath jsonb bool',
+  prosrc => 'jsonb_path_query_first_start' },
 { oid => '4009', descr => 'jsonpath match',
   proname => 'jsonb_path_match', prorettype => 'bool',
   proargtypes => 'jsonb jsonpath jsonb bool', prosrc => 'jsonb_path_match' },
diff --git a/src/include/utils/jsonb.h b/src/include/utils/jsonb.h
index 649a1644f24..50b3c65557f 100644
--- a/src/include/utils/jsonb.h
+++ b/src/include/utils/jsonb.h
@@ -294,6 +294,13 @@ struct JsonbValue
 	}			val;
 };
 
+typedef enum JsonbValueTarget
+{
+	JsonbValue_AsJsonbValue,
+	JsonbValue_AsJsonb,
+	JsonbValue_AsText
+} JsonbValueTarget;
+
 #define IsAJsonbScalar(jsonbval)	(((jsonbval)->type >= jbvNull && \
 									  (jsonbval)->type <= jbvBool) || \
 									  (jsonbval)->type == jbvDatetime)
@@ -428,12 +435,12 @@ extern const char *JsonbTypeName(JsonbValue *val);
 extern Datum jsonb_set_element(Jsonb *jb, Datum *path, int path_len,
 							   JsonbValue *newval);
 extern Datum jsonb_get_element(Jsonb *jb, Datum *path, int npath,
-							   bool *isnull, bool as_text);
+							   bool *isnull, JsonbValueTarget target);
 extern bool to_jsonb_is_immutable(Oid typoid);
 extern Datum jsonb_build_object_worker(int nargs, Datum *args, bool *nulls,
 									   Oid *types, bool absent_on_null,
 									   bool unique_keys);
 extern Datum jsonb_build_array_worker(int nargs, Datum *args, bool *nulls,
 									  Oid *types, bool absent_on_null);
-
+extern Datum jsonbvalue_covert(JsonbValue *jbv, JsonbValueTarget target);
 #endif							/* __JSONB_H__ */
diff --git a/src/test/regress/expected/jsonb.out b/src/test/regress/expected/jsonb.out
index 4a16d0dbafb..c6af7a59ccb 100644
--- a/src/test/regress/expected/jsonb.out
+++ b/src/test/regress/expected/jsonb.out
@@ -457,8 +457,114 @@ CREATE TEMP TABLE test_jsonb (
 );
 INSERT INTO test_jsonb VALUES
 ('scalar','"a scalar"'),
+('scalarint','2'),
 ('array','["zero", "one","two",null,"four","five", [1,2,3],{"f1":9}]'),
-('object','{"field1":"val1","field2":"val2","field3":null, "field4": 4, "field5": [1,2,3], "field6": {"f1":9}}');
+('object','{"field1":"val1","field2":"val2","field3":null, "field4": 4, "field5": [1,2,3], "field6": {"f1":9}, "field7": true, "field8": [1,2,3,4,5]}');
+\pset null NULL
+EXPLAIN (COSTS OFF, VERBOSE)
+SELECT
+(test_json -> 'field4')::numeric,
+(test_json -> 'field4')::int2,
+(test_json -> 'field4')::int4,
+(test_json -> 'field4')::int8,
+(test_json -> 'field4')::float4,
+(test_json -> 'field4')::float8,
+(test_json->'field5' -> 0)::numeric,
+(test_json->'field5' -> 10)::numeric,
+(test_json#>'{"field6", "f1"}')::numeric,
+(test_json#>'{"field6", "f2"}')::numeric,
+(test_json#>'{"field7"}')::bool
+FROM test_jsonb
+WHERE json_type = 'object';
+                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       QUERY PLAN                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ Seq Scan on pg_temp.test_jsonb
+   Output: jsonb_finish_numeric(jsonb_object_field_start((test_json)::internal, 'field4'::text), '1700'::oid), (jsonb_finish_numeric(jsonb_object_field_start((test_json)::internal, 'field4'::text), '21'::oid))::smallint, (jsonb_finish_numeric(jsonb_object_field_start((test_json)::internal, 'field4'::text), '23'::oid))::integer, (jsonb_finish_numeric(jsonb_object_field_start((test_json)::internal, 'field4'::text), '20'::oid))::bigint, (jsonb_finish_numeric(jsonb_object_field_start((test_json)::internal, 'field4'::text), '700'::oid))::real, (jsonb_finish_numeric(jsonb_object_field_start((test_json)::internal, 'field4'::text), '701'::oid))::double precision, jsonb_finish_numeric(jsonb_array_element_start(((test_json -> 'field5'::text))::internal, 0), '1700'::oid), jsonb_finish_numeric(jsonb_array_element_start(((test_json -> 'field5'::text))::internal, 10), '1700'::oid), jsonb_finish_numeric(jsonb_extract_path_start((test_json)::internal, VARIADIC '{field6,f1}'::text[]), '1700'::oid), jsonb_finish_numeric(jsonb_extract_path_start((test_json)::internal, VARIADIC '{field6,f2}'::text[]), '1700'::oid), jsonb_finish_bool(jsonb_extract_path_start((test_json)::internal, VARIADIC '{field7}'::text[]))
+   Filter: (test_jsonb.json_type = 'object'::text)
+(3 rows)
+
+SELECT
+(test_json -> 'field4')::numeric,
+(test_json -> 'field4')::int2,
+(test_json -> 'field4')::int4,
+(test_json -> 'field4')::int8,
+(test_json -> 'field4')::float4,
+(test_json -> 'field4')::float8,
+(test_json -> 'field5' -> 0)::numeric,
+(test_json -> 'field5' -> 10)::numeric,
+(test_json #> '{"field6", "f1"}')::numeric,
+(test_json #> '{"field6", "f2"}')::numeric,
+(test_json#>'{"field7"}')::bool
+FROM test_jsonb
+WHERE json_type = 'object';
+ numeric | int2 | int4 | int8 | float4 | float8 | numeric | numeric | numeric | numeric | bool 
+---------+------+------+------+--------+--------+---------+---------+---------+---------+------
+       4 |    4 |    4 |    4 |      4 |      4 |       1 |    NULL |       9 |    NULL | t
+(1 row)
+
+EXPLAIN (COSTS OFF, VERBOSE)
+SELECT
+jsonb_path_query(test_json,'$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}'),
+jsonb_path_query_first(test_json, '$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}'),
+jsonb_path_query(test_json,'$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}')::int2,
+jsonb_path_query_first(test_json, '$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}')::int2
+FROM test_jsonb
+WHERE json_type = 'object';
+                                                                                                                                                                                                                                                                                                                             QUERY PLAN                                                                                                                                                                                                                                                                                                                             
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ Result
+   Output: (jsonb_path_query(test_json, '$."field8"[*]?(@ >= $"min" && @ <= $"max")'::jsonpath, '{"max": 4, "min": 2}'::jsonb, false)), jsonb_path_query_first(test_json, '$."field8"[*]?(@ >= $"min" && @ <= $"max")'::jsonpath, '{"max": 4, "min": 2}'::jsonb, false), (jsonb_finish_numeric((jsonb_path_query_start((test_json)::internal, '$."field8"[*]?(@ >= $"min" && @ <= $"max")'::jsonpath, '{"max": 4, "min": 2}'::jsonb, false)), '21'::oid))::smallint, (jsonb_finish_numeric(jsonb_path_query_first_start((test_json)::internal, '$."field8"[*]?(@ >= $"min" && @ <= $"max")'::jsonpath, '{"max": 4, "min": 2}'::jsonb, false), '21'::oid))::smallint
+   ->  ProjectSet
+         Output: jsonb_path_query(test_json, '$."field8"[*]?(@ >= $"min" && @ <= $"max")'::jsonpath, '{"max": 4, "min": 2}'::jsonb, false), jsonb_path_query_start((test_json)::internal, '$."field8"[*]?(@ >= $"min" && @ <= $"max")'::jsonpath, '{"max": 4, "min": 2}'::jsonb, false), test_json
+         ->  Seq Scan on pg_temp.test_jsonb
+               Output: json_type, test_json
+               Filter: (test_jsonb.json_type = 'object'::text)
+(7 rows)
+
+SELECT
+jsonb_path_query(test_json,'$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}'),
+jsonb_path_query_first(test_json, '$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}'),
+jsonb_path_query(test_json,'$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}')::int2,
+jsonb_path_query_first(test_json, '$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}')::int2
+FROM test_jsonb
+WHERE json_type = 'object';
+ jsonb_path_query | jsonb_path_query_first | jsonb_path_query | jsonb_path_query_first 
+------------------+------------------------+------------------+------------------------
+ 2                | 2                      |                2 |                      2
+ 3                | 2                      |                3 |                      2
+ 4                | 2                      |                4 |                      2
+(3 rows)
+
+EXPLAIN (COSTS OFF, VERBOSE)
+SELECT (test_json #> '{}')::numeric FROM test_jsonb WHERE json_type = 'scalarint';
+                                                     QUERY PLAN                                                      
+---------------------------------------------------------------------------------------------------------------------
+ Seq Scan on pg_temp.test_jsonb
+   Output: jsonb_finish_numeric(jsonb_extract_path_start((test_json)::internal, VARIADIC '{}'::text[]), '1700'::oid)
+   Filter: (test_jsonb.json_type = 'scalarint'::text)
+(3 rows)
+
+SELECT (test_json #> '{}')::numeric FROM test_jsonb WHERE json_type = 'scalarint';
+ numeric 
+---------
+       2
+(1 row)
+
+-- let raise some errors.
+EXPLAIN (COSTS OFF, VERBOSE)
+SELECT (test_json -> 'field1')::int4 FROM test_jsonb WHERE json_type = 'object';
+                                                      QUERY PLAN                                                       
+-----------------------------------------------------------------------------------------------------------------------
+ Seq Scan on pg_temp.test_jsonb
+   Output: (jsonb_finish_numeric(jsonb_object_field_start((test_json)::internal, 'field1'::text), '23'::oid))::integer
+   Filter: (test_jsonb.json_type = 'object'::text)
+(3 rows)
+
+SELECT (test_json -> 'field1')::int4 FROM test_jsonb WHERE json_type = 'object';
+ERROR:  cannot cast jsonb string to type integer
+SELECT (test_json -> 'field1')::bool FROM test_jsonb WHERE json_type = 'object';
+ERROR:  cannot cast jsonb string to type boolean
+\pset null ''
 SELECT test_json -> 'x' FROM test_jsonb WHERE json_type = 'scalar';
  ?column? 
 ----------
@@ -586,7 +692,9 @@ SELECT jsonb_object_keys(test_json) FROM test_jsonb WHERE json_type = 'object';
  field4
  field5
  field6
-(6 rows)
+ field7
+ field8
+(8 rows)
 
 -- nulls
 SELECT (test_json->'field3') IS NULL AS expect_false FROM test_jsonb WHERE json_type = 'object';
diff --git a/src/test/regress/sql/jsonb.sql b/src/test/regress/sql/jsonb.sql
index e4b7cdf703d..500d04936d9 100644
--- a/src/test/regress/sql/jsonb.sql
+++ b/src/test/regress/sql/jsonb.sql
@@ -154,8 +154,72 @@ CREATE TEMP TABLE test_jsonb (
 
 INSERT INTO test_jsonb VALUES
 ('scalar','"a scalar"'),
+('scalarint','2'),
 ('array','["zero", "one","two",null,"four","five", [1,2,3],{"f1":9}]'),
-('object','{"field1":"val1","field2":"val2","field3":null, "field4": 4, "field5": [1,2,3], "field6": {"f1":9}}');
+('object','{"field1":"val1","field2":"val2","field3":null, "field4": 4, "field5": [1,2,3], "field6": {"f1":9}, "field7": true, "field8": [1,2,3,4,5]}');
+
+\pset null NULL
+EXPLAIN (COSTS OFF, VERBOSE)
+SELECT
+(test_json -> 'field4')::numeric,
+(test_json -> 'field4')::int2,
+(test_json -> 'field4')::int4,
+(test_json -> 'field4')::int8,
+(test_json -> 'field4')::float4,
+(test_json -> 'field4')::float8,
+(test_json->'field5' -> 0)::numeric,
+(test_json->'field5' -> 10)::numeric,
+(test_json#>'{"field6", "f1"}')::numeric,
+(test_json#>'{"field6", "f2"}')::numeric,
+(test_json#>'{"field7"}')::bool
+FROM test_jsonb
+WHERE json_type = 'object';
+
+SELECT
+(test_json -> 'field4')::numeric,
+(test_json -> 'field4')::int2,
+(test_json -> 'field4')::int4,
+(test_json -> 'field4')::int8,
+(test_json -> 'field4')::float4,
+(test_json -> 'field4')::float8,
+(test_json -> 'field5' -> 0)::numeric,
+(test_json -> 'field5' -> 10)::numeric,
+(test_json #> '{"field6", "f1"}')::numeric,
+(test_json #> '{"field6", "f2"}')::numeric,
+(test_json#>'{"field7"}')::bool
+FROM test_jsonb
+WHERE json_type = 'object';
+
+EXPLAIN (COSTS OFF, VERBOSE)
+SELECT
+jsonb_path_query(test_json,'$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}'),
+jsonb_path_query_first(test_json, '$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}'),
+jsonb_path_query(test_json,'$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}')::int2,
+jsonb_path_query_first(test_json, '$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}')::int2
+FROM test_jsonb
+WHERE json_type = 'object';
+
+SELECT
+jsonb_path_query(test_json,'$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}'),
+jsonb_path_query_first(test_json, '$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}'),
+jsonb_path_query(test_json,'$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}')::int2,
+jsonb_path_query_first(test_json, '$.field8[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}')::int2
+FROM test_jsonb
+WHERE json_type = 'object';
+
+
+EXPLAIN (COSTS OFF, VERBOSE)
+SELECT (test_json #> '{}')::numeric FROM test_jsonb WHERE json_type = 'scalarint';
+SELECT (test_json #> '{}')::numeric FROM test_jsonb WHERE json_type = 'scalarint';
+
+-- let raise some errors.
+EXPLAIN (COSTS OFF, VERBOSE)
+SELECT (test_json -> 'field1')::int4 FROM test_jsonb WHERE json_type = 'object';
+SELECT (test_json -> 'field1')::int4 FROM test_jsonb WHERE json_type = 'object';
+
+SELECT (test_json -> 'field1')::bool FROM test_jsonb WHERE json_type = 'object';
+
+\pset null ''
 
 SELECT test_json -> 'x' FROM test_jsonb WHERE json_type = 'scalar';
 SELECT test_json -> 'x' FROM test_jsonb WHERE json_type = 'array';
-- 
2.21.0

