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Loading a Graph from Two Database Tables
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Creating graph configuration
----------------------------

To load this graph into PGX, write a graphconfig. You can write the config in JSON format into a file:

.. compound::

  Notice that you will have to modify ``jdbc_url``, ``username`` and ``password`` according to your own database configuration.

.. code-block:: python
    :linenos:

    # To load this graph into PGX, write a graph config.
    # You can write the config in JSON format into a file
    json = '''{
        "format": "two_tables",
        "datastore": "rdbms",
        "jdbc_url": "jdbc:oracle:thin:@localhost:1521:rdbmsod",
        "username": "username",
        "password": "password",
        "keystore_alias": "database1",
        "nodes_table_name": "nodes",
        "edges_table_name": "edges",
        "error_handling": {
            "on_prop_conversion": "silent",
            "on_missed_prop_key": "log_warn_once"
        }
    }'''

Actual Graph Loading
--------------------

To load the graph data from the two tables into memory, simply write the graph config to :meth:`read_graph_with_properties()`. You can either write the path to the JSON file:

.. code-block:: python
    :linenos:

    # To load the graph data from the two tables into memory
    # You can either write the path to the JSON file:
    session = pypgx.get_session()
    path = self.pgx_test_resources + "/graph-confs/sample.csv.gz.json"
    graph = session.read_graph_with_properties(path)

or the config object directly if you built the config programmatically:

.. code-block:: python
    :linenos:

    session = pypgx.get_session("my-session")
    graph = session.read_graph_with_properties(config)