Add JSON_TABLE

Author: Nikita Glukhov

contrib/pg_stat_statements/pg_stat_statements.c

@@ -3227,9 +3227,11 @@ JumbleExpr(pgssJumbleState *jstate, Node *node)
 			{
 				TableFunc  *tablefunc = (TableFunc *) node;
 
+				APP_JUMB(tablefunc->functype);
 				JumbleExpr(jstate, tablefunc->docexpr);
 				JumbleExpr(jstate, tablefunc->rowexpr);
 				JumbleExpr(jstate, (Node *) tablefunc->colexprs);
+				JumbleExpr(jstate, (Node *) tablefunc->colvalexprs);
 			}
 			break;
 		case T_TableSampleClause:

src/backend/commands/explain.c

@@ -3575,7 +3575,9 @@ ExplainTargetRel(Plan *plan, Index rti, ExplainState *es)
 			break;
 		case T_TableFuncScan:
 			Assert(rte->rtekind == RTE_TABLEFUNC);
-			objectname = "xmltable";
+			objectname = rte->tablefunc ?
+				rte->tablefunc->functype == TFT_XMLTABLE ?
+				"xmltable" : "json_table" : NULL;
 			objecttag = "Table Function Name";
 			break;
 		case T_ValuesScan:

src/backend/executor/execExpr.c

@@ -2315,6 +2315,7 @@ ExecInitExprRec(Expr *node, ExprState *state,
 					var->typmod = exprTypmod((Node *) argexpr);
 					var->estate = ExecInitExpr(argexpr, state->parent);
 					var->econtext = NULL;
+					var->mcxt = NULL;
 					var->evaluated = false;
 					var->value = (Datum) 0;
 					var->isnull = true;

src/backend/executor/execExprInterp.c

@@ -4536,6 +4536,7 @@ ExecEvalJsonBehavior(ExprContext *econtext, JsonBehavior *behavior,
 
 		case JSON_BEHAVIOR_NULL:
 		case JSON_BEHAVIOR_UNKNOWN:
+		case JSON_BEHAVIOR_EMPTY:
 			*is_null = true;
 			return (Datum) 0;
 
@@ -4628,8 +4629,14 @@ EvalJsonPathVar(void *cxt, char *varName, int varNameLen,
 
 	if (!var->evaluated)
 	{
+		MemoryContext oldcxt = var->mcxt ?
+			MemoryContextSwitchTo(var->mcxt) : NULL;
+
 		var->value = ExecEvalExpr(var->estate, var->econtext, &var->isnull);
 		var->evaluated = true;
+
+		if (oldcxt)
+			MemoryContextSwitchTo(oldcxt);
 	}
 
 	if (var->isnull)
@@ -4772,6 +4779,7 @@ ExecEvalJsonExprSubtrans(JsonFunc func, ExprEvalStep *op,
 		PG_CATCH();
 		{
 			ErrorData  *edata;
+			int			ecategory;
 
 			/* Save error info in oldcontext */
 			MemoryContextSwitchTo(oldcontext);
@@ -4783,8 +4791,10 @@ ExecEvalJsonExprSubtrans(JsonFunc func, ExprEvalStep *op,
 			MemoryContextSwitchTo(oldcontext);
 			CurrentResourceOwner = oldowner;
 
-			if (ERRCODE_TO_CATEGORY(edata->sqlerrcode) !=
-				ERRCODE_DATA_EXCEPTION)
+			ecategory = ERRCODE_TO_CATEGORY(edata->sqlerrcode);
+
+			if (ecategory != ERRCODE_DATA_EXCEPTION &&
+				ecategory != ERRCODE_INTEGRITY_CONSTRAINT_VIOLATION)	/* domain errors */
 				ReThrowError(edata);
 
 			res = (Datum) 0;
@@ -4913,6 +4923,10 @@ ExecEvalJsonExpr(ExprEvalStep *op, ExprContext *econtext,
 				break;
 			}
 
+		case IS_JSON_TABLE:
+			*resnull = false;
+			return item;
+
 		default:
 			elog(ERROR, "unrecognized SQL/JSON expression op %d", jexpr->op);
 			return (Datum) 0;

src/backend/executor/nodeTableFuncscan.c

@@ -28,6 +28,7 @@
 #include "miscadmin.h"
 #include "nodes/execnodes.h"
 #include "utils/builtins.h"
+#include "utils/jsonpath.h"
 #include "utils/lsyscache.h"
 #include "utils/memutils.h"
 #include "utils/xml.h"
@@ -161,8 +162,9 @@ ExecInitTableFuncScan(TableFuncScan *node, EState *estate, int eflags)
 	scanstate->ss.ps.qual =
 		ExecInitQual(node->scan.plan.qual, &scanstate->ss.ps);
 
-	/* Only XMLTABLE is supported currently */
-	scanstate->routine = &XmlTableRoutine;
+	/* Only XMLTABLE and JSON_TABLE are supported currently */
+	scanstate->routine =
+		tf->functype == TFT_XMLTABLE ? &XmlTableRoutine : &JsonbTableRoutine;
 
 	scanstate->perTableCxt =
 		AllocSetContextCreate(CurrentMemoryContext,
@@ -381,14 +383,17 @@ tfuncInitialize(TableFuncScanState *tstate, ExprContext *econtext, Datum doc)
 		routine->SetNamespace(tstate, ns_name, ns_uri);
 	}
 
-	/* Install the row filter expression into the table builder context */
-	value = ExecEvalExpr(tstate->rowexpr, econtext, &isnull);
-	if (isnull)
-		ereport(ERROR,
-				(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
-				 errmsg("row filter expression must not be null")));
+	if (routine->SetRowFilter)
+	{
+		/* Install the row filter expression into the table builder context */
+		value = ExecEvalExpr(tstate->rowexpr, econtext, &isnull);
+		if (isnull)
+			ereport(ERROR,
+					(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+					 errmsg("row filter expression must not be null")));
 
-	routine->SetRowFilter(tstate, TextDatumGetCString(value));
+		routine->SetRowFilter(tstate, TextDatumGetCString(value));
+	}
 
 	/*
 	 * Install the column filter expressions into the table builder context.

src/backend/nodes/copyfuncs.c

@@ -1349,6 +1349,7 @@ _copyTableFunc(const TableFunc *from)
 {
 	TableFunc  *newnode = makeNode(TableFunc);
 
+	COPY_SCALAR_FIELD(functype);
 	COPY_NODE_FIELD(ns_uris);
 	COPY_NODE_FIELD(ns_names);
 	COPY_NODE_FIELD(docexpr);
@@ -1359,7 +1360,9 @@ _copyTableFunc(const TableFunc *from)
 	COPY_NODE_FIELD(colcollations);
 	COPY_NODE_FIELD(colexprs);
 	COPY_NODE_FIELD(coldefexprs);
+	COPY_NODE_FIELD(colvalexprs);
 	COPY_BITMAPSET_FIELD(notnulls);
+	COPY_NODE_FIELD(plan);
 	COPY_SCALAR_FIELD(ordinalitycol);
 	COPY_LOCATION_FIELD(location);
 
@@ -2615,6 +2618,76 @@ _copyJsonArgument(const JsonArgument *from)
 	return newnode;
 }
 
+/*
+ * _copyJsonTable
+ */
+static JsonTable *
+_copyJsonTable(const JsonTable *from)
+{
+	JsonTable *newnode = makeNode(JsonTable);
+
+	COPY_NODE_FIELD(common);
+	COPY_NODE_FIELD(columns);
+	COPY_NODE_FIELD(on_error);
+	COPY_NODE_FIELD(alias);
+	COPY_SCALAR_FIELD(location);
+
+	return newnode;
+}
+
+/*
+ * _copyJsonTableColumn
+ */
+static JsonTableColumn *
+_copyJsonTableColumn(const JsonTableColumn *from)
+{
+	JsonTableColumn *newnode = makeNode(JsonTableColumn);
+
+	COPY_SCALAR_FIELD(coltype);
+	COPY_STRING_FIELD(name);
+	COPY_NODE_FIELD(typeName);
+	COPY_STRING_FIELD(pathspec);
+	COPY_SCALAR_FIELD(format);
+	COPY_SCALAR_FIELD(wrapper);
+	COPY_SCALAR_FIELD(omit_quotes);
+	COPY_NODE_FIELD(columns);
+	COPY_NODE_FIELD(on_empty);
+	COPY_NODE_FIELD(on_error);
+	COPY_SCALAR_FIELD(location);
+
+	return newnode;
+}
+
+/*
+ * _copyJsonTableParentNode
+ */
+static JsonTableParentNode *
+_copyJsonTableParentNode(const JsonTableParentNode *from)
+{
+	JsonTableParentNode *newnode = makeNode(JsonTableParentNode);
+
+	COPY_NODE_FIELD(path);
+	COPY_NODE_FIELD(child);
+	COPY_SCALAR_FIELD(colMin);
+	COPY_SCALAR_FIELD(colMax);
+
+	return newnode;
+}
+
+/*
+ * _copyJsonTableSiblingNode
+ */
+static JsonTableSiblingNode *
+_copyJsonTableSiblingNode(const JsonTableSiblingNode *from)
+{
+	JsonTableSiblingNode *newnode = makeNode(JsonTableSiblingNode);
+
+	COPY_NODE_FIELD(larg);
+	COPY_NODE_FIELD(rarg);
+
+	return newnode;
+}
+
 /* ****************************************************************
  *						pathnodes.h copy functions
  *
@@ -5578,6 +5651,18 @@ copyObjectImpl(const void *from)
 		case T_JsonItemCoercions:
 			retval = _copyJsonItemCoercions(from);
 			break;
+		case T_JsonTable:
+			retval = _copyJsonTable(from);
+			break;
+		case T_JsonTableColumn:
+			retval = _copyJsonTableColumn(from);
+			break;
+		case T_JsonTableParentNode:
+			retval = _copyJsonTableParentNode(from);
+			break;
+		case T_JsonTableSiblingNode:
+			retval = _copyJsonTableSiblingNode(from);
+			break;
 
 			/*
 			 * RELATION NODES

src/backend/nodes/equalfuncs.c

@@ -120,6 +120,7 @@ _equalRangeVar(const RangeVar *a, const RangeVar *b)
 static bool
 _equalTableFunc(const TableFunc *a, const TableFunc *b)
 {
+	COMPARE_SCALAR_FIELD(functype);
 	COMPARE_NODE_FIELD(ns_uris);
 	COMPARE_NODE_FIELD(ns_names);
 	COMPARE_NODE_FIELD(docexpr);
@@ -130,13 +131,35 @@ _equalTableFunc(const TableFunc *a, const TableFunc *b)
 	COMPARE_NODE_FIELD(colcollations);
 	COMPARE_NODE_FIELD(colexprs);
 	COMPARE_NODE_FIELD(coldefexprs);
+	COMPARE_NODE_FIELD(colvalexprs);
 	COMPARE_BITMAPSET_FIELD(notnulls);
+	COMPARE_NODE_FIELD(plan);
 	COMPARE_SCALAR_FIELD(ordinalitycol);
 	COMPARE_LOCATION_FIELD(location);
 
 	return true;
 }
 
+static bool
+_equalJsonTableParentNode(const JsonTableParentNode *a, const JsonTableParentNode *b)
+{
+	COMPARE_NODE_FIELD(path);
+	COMPARE_NODE_FIELD(child);
+	COMPARE_SCALAR_FIELD(colMin);
+	COMPARE_SCALAR_FIELD(colMax);
+
+	return true;
+}
+
+static bool
+_equalJsonTableSiblingNode(const JsonTableSiblingNode *a, const JsonTableSiblingNode *b)
+{
+	COMPARE_NODE_FIELD(larg);
+	COMPARE_NODE_FIELD(rarg);
+
+	return true;
+}
+
 static bool
 _equalIntoClause(const IntoClause *a, const IntoClause *b)
 {
@@ -3479,6 +3502,12 @@ equal(const void *a, const void *b)
 		case T_JsonItemCoercions:
 			retval = _equalJsonItemCoercions(a, b);
 			break;
+		case T_JsonTableParentNode:
+			retval = _equalJsonTableParentNode(a, b);
+			break;
+		case T_JsonTableSiblingNode:
+			retval = _equalJsonTableSiblingNode(a, b);
+			break;
 
 			/*
 			 * RELATION NODES

src/backend/nodes/nodeFuncs.c

@@ -2352,6 +2352,8 @@ expression_tree_walker(Node *node,
 					return true;
 				if (walker(tf->coldefexprs, context))
 					return true;
+				if (walker(tf->colvalexprs, context))
+					return true;
 			}
 			break;
 		case T_JsonValueExpr:
@@ -3347,6 +3349,7 @@ expression_tree_mutator(Node *node,
 				MUTATE(newnode->rowexpr, tf->rowexpr, Node *);
 				MUTATE(newnode->colexprs, tf->colexprs, List *);
 				MUTATE(newnode->coldefexprs, tf->coldefexprs, List *);
+				MUTATE(newnode->colvalexprs, tf->colvalexprs, List *);
 				return (Node *) newnode;
 			}
 			break;
@@ -4291,6 +4294,30 @@ raw_expression_tree_walker(Node *node,
 					return true;
 			}
 			break;
+		case T_JsonTable:
+			{
+				JsonTable  *jt = (JsonTable *) node;
+
+				if (walker(jt->common, context))
+					return true;
+				if (walker(jt->columns, context))
+					return true;
+			}
+			break;
+		case T_JsonTableColumn:
+			{
+				JsonTableColumn  *jtc = (JsonTableColumn *) node;
+
+				if (walker(jtc->typeName, context))
+					return true;
+				if (walker(jtc->on_empty, context))
+					return true;
+				if (walker(jtc->on_error, context))
+					return true;
+				if (jtc->coltype == JTC_NESTED && walker(jtc->columns, context))
+					return true;
+			}
+			break;
 		default:
 			elog(ERROR, "unrecognized node type: %d",
 				 (int) nodeTag(node));