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In-place delta graph refresh
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This guide describes how you can set up a graph loaded from RDBMS Oracle Property Graph to be refreshed in-place.
Graphs that are updated in-place don't create a new **snapshot** of the graph when being refreshed in case the changes contain property updates only.
In case the graph has topological updates a new snapshot is generated anyway. Vertex label and edge label updates are also considered topological updates.

To use this feature, the flag ``update_properties_in_place`` should be set to true in the graph loading config

.. code-block:: json

  {
    "format": "pg",
    "jdbc_url": "jdbc:oracle:thin:@mydatabaseserver:1521/dbName",
    "username": "username",
    "password": "password",
    "name": "my_graph",
    "loading_options": {
      "auto_refresh": true,
      "fetch_interval_sec": 300,
      "update_interval_sec": 1200,
      "update_threshold": 1000,
      "create_edge_id_index": true,
      "create_edge_id_mapping": true,
      "update_properties_in_place": true
    }
  }

Analysis tasks (pgql queries and Green marl algorithms) are delayed if an in-place update for the requested graph is happening.
If an analytic task is running while an in-place update is applied users can select the consistency model that should be used, we support two models: ``ALLOW_INCONSISTENCIES`` the default behavior which keeps the running tasks, it might lead to unexpected results. The second model is ``CANCEL_TASKS``: tasks running during an update will get canceled, new tasks will get delayed.