You must first load a graph to work with datetime data. See Reading Graphs from Database into the Graph Server (PGX) for more information on graph loading.

The following example shows how to load a graph that has three vertices representing persons and zero edges.

1. Create a SQL property graph using datetime data stored in emp table as shown:

   CREATE TABLE emp (
     id          NUMBER (10) NOT NULL
     name        VARCHAR2(10),
   j joined_on   TIMESTAMP,
     CONSTRAINT  emp_pk PRIMARY KEY (id)
   );
   
   INSERT into emp values (100, "John", to_timestamp('1990-02-02 09:30:00', 'YYYY-MM-DD HH:MI:SS');
   INSERT into emp values (200, "Mary", to_timestamp('2000-07-01 10:15:20', 'YYYY-MM-DD HH:MI:SS');
   INSERT into emp values (300, "Alice", to_timestamp('2014-10-10 11:00:00', 'YYYY-MM-DD HH:MI:SS');
   
   CREATE PROPERTY GRAPH emp_graph
     VERTEX TABLES (
      emp
        KEY ( id )
        LABEL emp
        PROPERTIES ( id, name, joined_on )
   );

2. Load the graph into the graph server (PGX) and optionally, query the graph.

opg4j> var g = session.readGraphByName ("EMP_GRAPH",GraphSource.PG_SQL)
opg4j> g.queryPgql("SELECT n.* FROM MATCH (n)").print()
+-----------------------------------+
| ID  | NAME  | JOINED_ON           |
+-----------------------------------+
| 200 | Mary  | 2000-07-01T10:15:20 |
| 100 | John  | 1990-02-02T09:30    |
| 300 | Alice | 2014-10-10T11:00    |
+-----------------------------------+
$3 ==> PgqlResultSetImpl[graph=EMP_GRAPH,numResults=3]

PgxGraph g = session.readGraphByName("EMP_GRAPH", GraphSource.PG_SQL);
PgqlResultSet resultSet = g.queryPgql("SELECT n.* FROM MATCH (n)");
resultSet.print();

>>> g = session.read_graph_by_name("EMP_GRAPH", "pg_sql")
>>> g = session.read_graph_by_name("EMP_GRAPH", "pg_sql")
+-----------------------------------+
| ID  | NAME  | JOINED_ON           |
+-----------------------------------+
| 200 | Mary  | 2000-07-01T10:15:20 |
| 100 | John  | 1990-02-02T09:30    |
| 300 | Alice | 2014-10-10T11:00    |
+-----------------------------------+