Support CREATE VLABEL Command with no hierarchy

Author: JoshInnis

postgraph--0.1.0.sql

@@ -138,8 +138,9 @@ RETURNS void
 LANGUAGE c 
 AS 'MODULE_PATHNAME';
 
-CREATE FUNCTION create_vlabel(graph_name name, label_name name) 
+CREATE FUNCTION create_vlabel(graph_name text, label_name text) 
 RETURNS void 
+RETURNS NULL ON NULL INPUT
 LANGUAGE c 
 AS 'MODULE_PATHNAME';
 

regress/expected/cypher_create.out

@@ -48,6 +48,25 @@ MATCH () RETURN 1;
  1
 (1 row)
 
+CREATE VLABEL test;
+NOTICE:  VLabel "test" has been created
+ create_vlabel 
+---------------
+ 
+(1 row)
+
+SELECT * FROM postgraph.ag_label;
+       name       | graph | id | kind |            relation            |           vertex_adjlist            |      label_path       
+------------------+-------+----+------+--------------------------------+-------------------------------------+-----------------------
+ _ag_label_vertex | 18780 |  1 | v    | 18783                          | 18792                               | _ag_label_vertex
+ _ag_label_edge   | 18780 |  2 | e    | 18796                          |                                     | _ag_label_edge
+ _ag_label_vertex | 18805 |  1 | v    | 18808                          | 18817                               | _ag_label_vertex
+ _ag_label_edge   | 18805 |  2 | e    | 18821                          |                                     | _ag_label_edge
+ _ag_label_vertex | 18833 |  1 | v    | cypher_create._ag_label_vertex | cypher_create._adj__ag_label_vertex | _ag_label_vertex
+ _ag_label_edge   | 18833 |  2 | e    | cypher_create._ag_label_edge   |                                     | _ag_label_edge
+ test             | 18833 |  3 | v    | cypher_create.test             | cypher_create._adj_test             | _ag_label_vertex.test
+(7 rows)
+
 CREATE ()-[]->();
 ERROR:  CREATE doesn't work with paths
 CYPHER WITH 1 as a
@@ -59,10 +78,12 @@ ERROR:  CREATE doesn't work with next clauses
 -- Clean up
 --
 DROP GRAPH cypher_create CASCADE;
-NOTICE:  drop cascades to 3 other objects
+NOTICE:  drop cascades to 5 other objects
 DETAIL:  drop cascades to table cypher_create._ag_label_vertex
 drop cascades to table cypher_create._adj__ag_label_vertex
 drop cascades to table cypher_create._ag_label_edge
+drop cascades to table cypher_create.test
+drop cascades to table cypher_create._adj_test
 NOTICE:  graph "cypher_create" has been dropped
  drop_graph 
 ------------

regress/sql/cypher_create.sql

@@ -29,6 +29,9 @@ SELECT * FROM cypher_create._ag_label_vertex;
 
 MATCH () RETURN 1;
 
+CREATE VLABEL test;
+SELECT * FROM postgraph.ag_label;
+
 CREATE ()-[]->();
 
 CYPHER WITH 1 as a

src/backend/commands/label_commands.c

@@ -97,81 +97,45 @@ static char *make_vertex_adjlist_alias(char *var_name);
 
 
 PG_FUNCTION_INFO_V1(create_vlabel);
-
-/*
- * This is a callback function
- * This function will be called when the user will call SELECT create_vlabel.
- * The function takes two parameters
- * 1. Graph name
- * 2. Label Name
- * Function will create a vertex label
- * Function returns an error if graph or label names or not provided
-*/
-
 Datum create_vlabel(PG_FUNCTION_ARGS)
 {
     char *graph;
-    Name graph_name;
+    text * graph_name;
     char *graph_name_str;
     Oid graph_oid;
     List *parent;
 
     RangeVar *rv;
 
     char *label;
-    Name label_name;
+    text * label_name;
     char *label_name_str;
 
-    // checking if user has not provided the graph name
-    if (PG_ARGISNULL(0))
-    {
-        ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-                errmsg("graph name must not be NULL")));
-    }
-
-    // checking if user has not provided the label name
-    if (PG_ARGISNULL(1))
-    {
-        ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-                errmsg("label name must not be NULL")));
-    }
-
-    graph_name = PG_GETARG_NAME(0);
-    label_name = PG_GETARG_NAME(1);
+    graph_name = PG_GETARG_TEXT_PP(0);
+    label_name = PG_GETARG_TEXT_PP(1);
 
-    graph_name_str = NameStr(*graph_name);
-    label_name_str = NameStr(*label_name);
+    graph_name_str = text_to_cstring(graph_name);
+    label_name_str = text_to_cstring(label_name);
 
     // Check if graph does not exist
     if (!graph_exists(graph_name_str))
-    {
-        ereport(ERROR,
-                (errcode(ERRCODE_UNDEFINED_SCHEMA),
-                        errmsg("graph \"%s\" does not exist.", graph_name_str)));
-    }
+        ereport(ERROR, (errcode(ERRCODE_UNDEFINED_SCHEMA),
+                errmsg("graph \"%s\" does not exist.", graph_name_str)));
 
     graph_oid = get_graph_oid(graph_name_str);
 
     // Check if label with the input name already exists
     if (label_exists(label_name_str, graph_oid))
-    {
-        ereport(ERROR,
-                (errcode(ERRCODE_UNDEFINED_SCHEMA),
-                        errmsg("label \"%s\" already exists", label_name_str)));
-    }
-
-    //Create the default label tables
-    graph = graph_name->data;
-    label = label_name->data;
+        ereport(ERROR, (errcode(ERRCODE_UNDEFINED_SCHEMA),
+                errmsg("label \"%s\" already exists", label_name_str)));
 
-    rv = get_label_range_var(graph, graph_oid, AG_DEFAULT_LABEL_VERTEX);
+    rv = get_label_range_var(graph_name_str, graph_oid, AG_DEFAULT_LABEL_VERTEX);
 
     parent = list_make1(rv);
 
-    create_label(graph, label, LABEL_TYPE_VERTEX, parent, NULL);
+    create_label(graph_name_str, label_name_str, LABEL_TYPE_VERTEX, parent, NULL);
 
-    ereport(NOTICE,
-            (errmsg("VLabel \"%s\" has been created", NameStr(*label_name))));
+    ereport(NOTICE, (errmsg("VLabel \"%s\" has been created", label_name_str)));
 
     PG_RETURN_VOID();
 }

src/backend/nodes/ag_nodes.c

@@ -67,7 +67,8 @@ const char *node_names[] = {
     "cypher_create_graph",
     "cypher_use_graph",
     "cypher_drop_graph",
-    "cypher_label_tree_node"
+    "cypher_label_tree_node",
+    "cypher_create_vlabel"
 };
 
 /*
@@ -137,7 +138,8 @@ const ExtensibleNodeMethods node_methods[] = {
     DEFINE_NODE_METHODS(cypher_create_graph),
     DEFINE_NODE_METHODS(cypher_use_graph),
     DEFINE_NODE_METHODS(cypher_drop_graph),
-    DEFINE_NODE_METHODS(cypher_label_tree_node)
+    DEFINE_NODE_METHODS(cypher_label_tree_node),
+    DEFINE_NODE_METHODS(cypher_create_vlabel)
 };
 
 static bool equal_ag_node(const ExtensibleNode *a, const ExtensibleNode *b)

src/backend/nodes/cypher_outfuncs.c

@@ -468,6 +468,14 @@ void out_cypher_drop_graph(StringInfo str, const ExtensibleNode *node)
     WRITE_BOOL_FIELD(cascade);
 }
 
+void out_cypher_create_vlabel(StringInfo str, const ExtensibleNode *node)
+{
+    DEFINE_AG_NODE(cypher_create_vlabel);
+
+    WRITE_STRING_FIELD(label_name);
+}
+
+
 /*
  * Copied from Postgres
  *

src/backend/nodes/cypher_readfuncs.c

@@ -322,4 +322,12 @@ void read_cypher_drop_graph(struct ExtensibleNode *node)
 
     READ_STRING_FIELD(graph_name);
     READ_BOOL_FIELD(cascade);
+}
+
+
+void read_cypher_create_vlabel(struct ExtensibleNode *node)
+{
+    READ_LOCALS(cypher_create_vlabel);
+
+    READ_STRING_FIELD(label_name);
 }

src/backend/parser/cypher_analyze.c

@@ -78,6 +78,9 @@ static FuncExpr *make_clause_create_graph_func_expr(char *graph_name);
 static Query *cypher_create_graph_utility(ParseState *pstate, const char *graph_name);
 static FuncExpr *make_clause_use_graph_func_expr(char *graph_name);
 static Query *cypher_use_graph_utility(ParseState *pstate, const char *graph_name);
+static FuncExpr *make_clause_create_vlabel_func_expr(char *label_name);
+static Query *cypher_create_vlabel_utility(ParseState *pstate, const char *label_name);
+
 static Oid get_session_graph_oid();
 static CommandTag
 CypherCreateCommandTag(Node *parsetree);
@@ -1223,6 +1226,10 @@ cypher_parse_analyze(RawStmt *parseTree, const char *sourceText,
         cypher_drop_graph *ccg = n;
 
         query = cypher_drop_graph_utility(pstate, ccg->graph_name);
+    } else if (is_ag_node(n, cypher_create_vlabel)) {
+        cypher_create_vlabel *ccg = n;
+
+        query = cypher_create_vlabel_utility(pstate, ccg->label_name);
     } else {
         query = parse_analyze((makeRawStmt(n, 0)), sourceText, paramTypes, numParams, queryEnv);
 
@@ -1452,6 +1459,47 @@ cypher_use_graph_utility(ParseState *pstate, const char *graph_name) {
     return query;
 }
 
+
+
+/*
+ * Creates the function expression that represents the clause. Adds the
+ * extensible node that represents the metadata that the clause needs to
+ * handle the clause in the execution phase.
+ */
+static FuncExpr *make_clause_create_vlabel_func_expr(char *label_name) {
+
+    graph_cache_data *gcd = search_graph_namespace_cache(get_session_graph_oid());
+
+    Const *c = makeConst(TEXTOID, -1, InvalidOid, strlen(label_name), CStringGetTextDatum(label_name), false, false);
+    Const *c1 = makeConst(TEXTOID, -1, InvalidOid, strlen(gcd->name.data), CStringGetTextDatum(gcd->name.data), false, false);
+
+
+    Oid func_oid = get_ag_func_oid("create_vlabel", 2, TEXTOID, TEXTOID);
+
+    return makeFuncExpr(func_oid, VOIDOID, list_make2(c1, c), InvalidOid, InvalidOid, COERCE_EXPLICIT_CALL);
+}
+
+static Query *
+cypher_create_vlabel_utility(ParseState *pstate, const char *label_name) {
+    Query *query;
+    TargetEntry *tle;
+    FuncExpr *func_expr;
+
+    query = makeNode(Query);
+    query->commandType = CMD_SELECT;
+    query->targetList = NIL;
+
+    func_expr = make_clause_create_vlabel_func_expr(label_name);
+
+    // Create the target entry
+    tle = makeTargetEntry((Expr *)func_expr, pstate->p_next_resno++, "create_vlabel", false);
+    query->targetList = lappend(query->targetList, tle);
+
+    query->rtable = pstate->p_rtable;
+    query->jointree = makeFromExpr(pstate->p_joinlist, NULL);
+    return query;
+}
+
 Oid get_session_graph_oid()
 {
     ScanKeyData scan_keys[1];

src/backend/parser/cypher_clause.c

@@ -808,11 +808,9 @@ static void transform_match_pattern(cypher_parsestate *cpstate, Query *query, Li
         bool is_null;
         rel_name = heap_getattr(tuple, Anum_ag_label_name, RelationGetDescr(label_catalog), &is_null);
 
-
         systable_endscan(scan_desc);
         table_close(label_catalog, AccessShareLock);
 
-
         //rel_name = get_label_relation_name(node->label, cpstate->graph_oid);
         label_range_var = makeRangeVar(schema_name, rel_name, -1);
         alias = makeAlias(node->name, NIL);
@@ -823,7 +821,6 @@ static void transform_match_pattern(cypher_parsestate *cpstate, Query *query, Li
         addNSItemToQuery(pstate, pnsi, true, true, true);
 
         resno = pstate->p_next_resno++;
-
         // XXX: End LTree Code here
 
         expr = (Expr *)make_vertex_expr(cpstate, pnsi);
@@ -839,9 +836,7 @@ static void transform_match_pattern(cypher_parsestate *cpstate, Query *query, Li
         te = makeTargetEntry(id, resno, make_id_alias(node->name), false);
         query->targetList = lappend(query->targetList, te);
 
-        /*
-        * properties field
-        */
+        // properties field
         Node *props = scanNSItemForColumn(pstate, pnsi, 0, AG_VERTEX_COLNAME_PROPERTIES, -1);
         resno = pstate->p_next_resno++;
 

src/backend/parser/cypher_gram.y

@@ -291,7 +291,7 @@ makeSimpleCypherA_Expr(A_Expr_Kind kind, char *name,
 	UNLISTEN UNLOGGED UNTIL UNWIND UPDATE USE USER USING
 
 	VACUUM VALID VALIDATE VALIDATOR VALUE_P VALUES VARCHAR VARIADIC VARYING
-	VERBOSE VERSION_P VIEW VIEWS VOLATILE
+	VERBOSE VERSION_P VIEW VIEWS VLABEL VOLATILE
 
 	WHEN WHERE WHITESPACE_P WINDOW WITH WITHIN WITHOUT WORK WRAPPER WRITE
 
@@ -345,7 +345,7 @@ makeSimpleCypherA_Expr(A_Expr_Kind kind, char *name,
 		CreateMatViewStmt RefreshMatViewStmt CreateAmStmt
 		CreatePublicationStmt AlterPublicationStmt
 		CreateSubscriptionStmt AlterSubscriptionStmt DropSubscriptionStmt
-		CreateGraphStmt UseGraphStmt DropGraphStmt
+		CreateGraphStmt CreateVLabelStmt UseGraphStmt DropGraphStmt
 
 %type <node> select_no_parens select_with_parens select_clause
              simple_select
@@ -936,6 +936,7 @@ toplevel_stmt:
 stmt:
            	CYPHER cypher_stmt { $$ = (Node *)$2; } 
 			| CreateGraphStmt
+			| CreateVLabelStmt
 			| DropGraphStmt
 			| UseGraphStmt
 			| AlterEventTrigStmt
@@ -11431,7 +11432,18 @@ CreateGraphStmt:
             $$ = (Node *)n;
         }
         ;
+		
+CreateVLabelStmt:
+    CREATE VLABEL BareColLabel
+        {
+
+            cypher_create_vlabel *n;
+            n = make_ag_node(cypher_create_vlabel);
+            n->label_name = $3;
 
+            $$ = (Node *)n;
+        }
+        ;
 
 /*****************************************************************************
  *