Graphs

A graph consists of a set of vertices and edges, where each individual node and edge possesses a map of properties. A vertex is the basic object of a graph, that can exist independently of everything else in the graph. An edge creates a directed connection between two vertices.

Create a Graph

To create a graph, use the create_graph function, located in the ag_catalog namespace.

create_graph()

Syntax: create_graph(graph_name);

Returns:

void

Arguments:

Name	Description
graph_name	Name of the graph to be created

Considerations

• This function will not return any results. The graph is created if there is no error message.

• Tables needed to set up the graph are automatically created.

Example:

SELECT * FROM ag_catalog.create_graph('graph_name');

Delete a Graph

To delete a graph, use the drop_graph function, located in the ag_catalog namespace.

drop_graph()

Syntax: drop_graph(graph_name, cascade);

Returns:

void

Arguments:

Name	Description
graph_name	Name of the graph to be deleted
cascade	A boolean that will will delete labels and data that depend on the graph.

Considerations:

• This function will not return any results. If there is no error message the graph has been deleted.

• It is recommended to set the cascade option to true, otherwise everything in the graph must be manually dropped with SQL DDL commands.

Example:

SELECT * FROM ag_catalog.drop_graph('graph_name', true);

A Cypher Graph vs A Postgres Namespace

Cypher uses a Postgres namespace for every individual graph. It is recommended that no DML or DDL commands are executed in the namespace that is reserved for the graph.