15.3 Exporting Graphs Into a File

The graph server (PGX) allows the client to export a currently loaded graph into a file.

Using the store() method on any PgxGraph object, the client can specify which file format to store the graph in. The client can also dynamically select the set of properties to be stored with the graph, that is, not all the properties need to be exported. The client can specify a CompressionScheme to use when storing as shown:

Table 15-20 Files CompressionScheme

CompressionScheme	Supported Formats
NONE	All formats
GZIP	ADJ_LIST, EDGE_LIST, FLAT_FILE, TWO_TABLES (text)

The client can export to multiple files as well.

When PGX exports the specified graph into a file, PGX also creates a graph config which the client receives as return value. This is to help loading the created graph instance later.

When exporting graph data into multiple files a FileGraphStoringConfig can be used which contains the following JSON fields:

Table 15-21 Graph Configuration when Exporting Graph into Multiple Files

Field	Type	Description	Default
base_path	string	Base path to use for storing a graph; file paths will be constructed using the following format _._, that is, parent_path/my_graph_1.edges.	null
compression_scheme	enum[none, gzip]	The scheme to use for compression, or none to disable compression.	none
delimiter	character	Delimiter character used as separator when storing. The characters ", {, } and \n cannot be used as delimiters.	null
edge_extension	string	The extension to use when creating edge file partitions.	edges
initial_partition_index	integer	The value used as initial partition index, that is, initial_partition_index=1024 -> my_graph_1024.edges, my_graph_1025.edges.	1
num_partitions	integer	The number of partitions that should be created, when exporting to multiple files.	1
row_extension	string	The extension to use when creating row file partitions.	rows
vertex_extension	string	The extension to use when creating vertex file partitions.	nodes

• Exporting a Graph to Disk