Implement CREATE GRAPH

First draft of create graph logic.

Author: JoshInnis

Makefile

@@ -86,42 +86,7 @@ EXTENSION = postgraph
 
 DATA = postgraph--0.1.0.sql
 
-# sorted in dependency order
-REGRESS = graphid \
-          gtype \
-	  network \
-          temporal \
-          range \
-          vertex \
-          edge \
-          variable_edge \
-          traversal \
-          catalog \
-          cypher  \
-          lists\
-          expr \
-	  vector \
-          cypher_create \
-          cypher_match \
-          cypher_unwind \
-          cypher_set \
-          cypher_remove \
-          cypher_delete \
-          cypher_with \
-          cypher_vle \
-          cypher_union \
-          cypher_merge \
-          cypher_call \
-          order_by \
-	  regex \
-          tsearch \
-          aggregation \
-          traversal_functions \
-          variable_edge_functions \
-	  geometric \
-          postgis \
-          index \
-          drop
+REGRESS = new_cypher
 
 srcdir=`pwd`
 POSTGIS_DIR ?= postgis_dir

regress/expected/new_cypher.out

@@ -0,0 +1,5 @@
+LOAD 'postgraph';
+
+CREATE GRAPH new_cypher;
+
+CREATE (n);

regress/sql/new_cypher.sql

@@ -99,7 +99,7 @@ AS 'MODULE_PATHNAME';
 --
 -- utility functions
 --
-CREATE FUNCTION create_graph(graph_name name)
+CREATE FUNCTION create_graph(graph_name text)
 RETURNS void 
 LANGUAGE c 
 AS 'MODULE_PATHNAME';

sql/postgraph.sql.in

@@ -37,6 +37,7 @@
 #include "parser/parser.h"
 #include "utils/rel.h"
 #include "utils/relcache.h"
+#include "utils/builtins.h"
 
 #include "catalog/ag_graph.h"
 #include "catalog/ag_label.h"
@@ -49,7 +50,7 @@
  */
 #define gen_graph_namespace_name(graph_name) (graph_name)
 
-static Oid create_schema_for_graph(const Name graph_name);
+static Oid create_schema_for_graph(const char *graph_name);
 static void drop_schema_for_graph(char *graph_name_str, const bool cascade);
 static void remove_schema(Node *schema_name, DropBehavior behavior);
 static void rename_graph(const Name graph_name, const Name new_name);
@@ -105,41 +106,42 @@ Datum create_graph(PG_FUNCTION_ARGS)
     Oid nsp_id;
 
     if (PG_ARGISNULL(0))
-    {
         ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("graph name must not be NULL")));
-    }
+
+    /*
     graph_name = PG_GETARG_NAME(0);
 
-    graph_name_str = NameStr(*graph_name);
+    graph_name_str = NameStr(*graph_name);*/
+    graph_name_str =  TextDatumGetCString(PG_GETARG_DATUM(0));
     if (graph_exists(graph_name_str))
-    {
         ereport(ERROR,
                 (errcode(ERRCODE_UNDEFINED_SCHEMA),
                         errmsg("graph \"%s\" already exists", graph_name_str)));
-    }
 
-    nsp_id = create_schema_for_graph(graph_name);
+    nsp_id = create_schema_for_graph(graph_name_str);
 
-    insert_graph(graph_name, nsp_id);
+    insert_graph(graph_name_str, nsp_id);
 
     //Increment the Command counter before create the generic labels.
     CommandCounterIncrement();
 
     //Create the default label tables
-    graph = graph_name->data;
+    graph = graph_name_str;//graph_name->data;
     create_label(graph, AG_DEFAULT_LABEL_VERTEX, LABEL_TYPE_VERTEX, NIL);
     create_label(graph, AG_DEFAULT_LABEL_EDGE, LABEL_TYPE_EDGE, NIL);
 
     ereport(NOTICE,
-            (errmsg("graph \"%s\" has been created", NameStr(*graph_name))));
+            (errmsg("graph \"%s\" has been created", graph_name_str)));
 
+    PopActiveSnapshot();
+    
     PG_RETURN_VOID();
 }
 
-static Oid create_schema_for_graph(const Name graph_name)
+static Oid create_schema_for_graph(const char * graph_name)
 {
-    char *graph_name_str = NameStr(*graph_name);
+    char *graph_name_str = graph_name;
     CreateSchemaStmt *schema_stmt;
     CreateSeqStmt *seq_stmt;
     TypeName *integer;

src/backend/commands/graph_commands.c

@@ -62,7 +62,8 @@ const char *node_names[] = {
     "cypher_update_item",
     "cypher_delete_information",
     "cypher_delete_item",
-    "cypher_merge_information"
+    "cypher_merge_information",
+    "cypher_create_graph"
 };
 
 /*
@@ -127,7 +128,8 @@ const ExtensibleNodeMethods node_methods[] = {
     DEFINE_NODE_METHODS_EXTENDED(cypher_update_item),
     DEFINE_NODE_METHODS_EXTENDED(cypher_delete_information),
     DEFINE_NODE_METHODS_EXTENDED(cypher_delete_item),
-    DEFINE_NODE_METHODS_EXTENDED(cypher_merge_information)
+    DEFINE_NODE_METHODS_EXTENDED(cypher_merge_information),
+    DEFINE_NODE_METHODS(cypher_create_graph),
 };
 
 static bool equal_ag_node(const ExtensibleNode *a, const ExtensibleNode *b)

src/backend/nodes/ag_nodes.c

@@ -427,6 +427,14 @@ void out_cypher_merge_information(StringInfo str, const ExtensibleNode *node)
     WRITE_NODE_FIELD(path);
 }
 
+// serialization function for the cypher_node ExtensibleNode.
+void out_cypher_create_graph(StringInfo str, const ExtensibleNode *node)
+{
+    DEFINE_AG_NODE(cypher_create_graph);
+
+    WRITE_STRING_FIELD(graph_name);
+}
+
 /*
  * Copied from Postgres
  *

src/backend/nodes/cypher_outfuncs.c

@@ -299,3 +299,11 @@ void read_cypher_merge_information(struct ExtensibleNode *node)
     READ_INT_FIELD(merge_function_attr);
     READ_NODE_FIELD(path);
 }
+
+
+void read_cypher_create_graph(struct ExtensibleNode *node)
+{
+    READ_LOCALS(cypher_create_graph);
+
+    READ_STRING_FIELD(graph_name);
+}

src/backend/nodes/cypher_readfuncs.c

@@ -103,10 +103,10 @@ makeRawStmt(Node *stmt, int stmt_location)
 static List *cypher_parse(char *string){
 	List	   *raw_parsetree_list;
 
-	TRACE_POSTGRESQL_QUERY_PARSE_START(string);
+	//TRACE_POSTGRESQL_QUERY_PARSE_START(string);
 
-	if (log_parser_stats)
-		ResetUsage();
+	//if (log_parser_stats)
+		//ResetUsage();
 /*
 	raw_parsetree_list = raw_parser(string, RAW_PARSE_DEFAULT);
 
@@ -148,7 +148,7 @@ static List *cypher_parse(char *string){
 	 * here.
 	 */
 
-	TRACE_POSTGRESQL_QUERY_PARSE_DONE(string);
+	//TRACE_POSTGRESQL_QUERY_PARSE_DONE(string);
 
 	return raw_parsetree_list;
 }
@@ -162,6 +162,39 @@ void parse_analyze_fini(void){
    parse_analyze_hook = NULL;
 }
 
+/*
+ * 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_graph_func_expr(char *graph_name) {
+    Const *c = makeConst(TEXTOID, -1, InvalidOid, strlen(graph_name), CStringGetTextDatum(graph_name), false, false);
+
+    Oid func_oid = get_ag_func_oid("create_graph", 1, TEXTOID);
+
+    return makeFuncExpr(func_oid, VOIDOID, list_make1(c), InvalidOid, InvalidOid, COERCE_EXPLICIT_CALL);
+}
+
+static Query *
+cypher_create_graph_utility(ParseState *pstate, const char *graph_name) {
+    Query *query;
+    TargetEntry *tle;
+    FuncExpr *func_expr;
+
+    query = makeNode(Query);
+    query->commandType = CMD_SELECT;
+    query->targetList = NIL;
+
+    func_expr = make_clause_create_graph_func_expr(graph_name);
+
+    // Create the target entry
+    tle = makeTargetEntry((Expr *)func_expr, pstate->p_next_resno++, "create_graph", false);
+    query->targetList = lappend(query->targetList, tle);
+
+    query->rtable = pstate->p_rtable;
+    query->jointree = makeFromExpr(pstate->p_joinlist, NULL);
+    return query;
+}
 
 /*
  * parse_analyze
@@ -193,6 +226,28 @@ cypher_parse_analyze(RawStmt *parseTree, const char *sourceText,
 	pstate->p_queryEnv = queryEnv;
 
 	//query = transformTopLevelStmt(pstate, parseTree);
+    if (list_length(parseTree->stmt) == 1) {
+      Node *n = linitial(parseTree->stmt);
+
+      if (is_ag_node(n, cypher_create_graph)) {
+        cypher_create_graph *ccg = n;
+        //ereport(ERROR, errmsg("Here"));
+
+        query = cypher_create_graph_utility(pstate, ccg->graph_name);
+
+        query->canSetTag = true;
+
+        if (IsQueryIdEnabled())
+		  jstate = JumbleQuery(query, sourceText);
+
+	    free_parsestate(pstate);
+
+	    pgstat_report_query_id(query->queryId, false);
+		PushActiveSnapshot(GetTransactionSnapshot());
+	    return query;
+
+      }
+    }
     query = analyze_cypher(parseTree->stmt, pstate, sourceText, 0, NULL, CurrentGraphOid, NULL);
 
     if (IsQueryIdEnabled())

src/backend/parser/cypher_analyze.c

@@ -89,7 +89,7 @@
                  CALL CASE COALESCE CONTAINS CREATE CUBE CURRENT CURRENT_DATE CURRENT_TIME CURRENT_TIMESTAMP
                  DATE DECADE DELETE DESC DESCENDING DETACH DISTINCT
                  ELSE END_P ENDS EXCEPT EXCLUDE EXISTS EXTRACT
-                 GROUP GROUPS GROUPING
+                 GRAPH GROUP GROUPS GROUPING
                  FALSE_P FILTER FIRST_P FOLLOWING FROM
                  HAVING
                  ILIKE IN INTERSECT INTERVAL IS
@@ -252,8 +252,8 @@ stmt:
              *
              * Throw syntax error in this case.
              */
-            if (yychar != YYEOF)
-                yyerror(&yylloc, scanner, extra, "syntax error");
+            //if (yychar != YYEOF)
+                //yyerror(&yylloc, scanner, extra, "syntax error");
 
             extra->result = $1;
         }
@@ -385,6 +385,7 @@ yield_item:
 semicolon_opt:
     /* empty */
     | ';'
+
     ;
 
 all_or_distinct:
@@ -922,7 +923,6 @@ unwind:
 /*
  * CREATE clause
  */
-
 create:
     CREATE pattern
         {
@@ -931,6 +931,15 @@ create:
             n = make_ag_node(cypher_create);
             n->pattern = $2;
 
+            $$ = (Node *)n;
+        }
+    | CREATE GRAPH IDENTIFIER
+        {
+
+            cypher_create_graph *n;
+            n = make_ag_node(cypher_create_graph);
+            n->graph_name = $3;
+
             $$ = (Node *)n;
         }
     ;