Database

The database class is used to create and manage the Kùzu database instance.

class Database()

Available APIs:

• __init__
• resize_buffer_manager Resize the mamimum size of buffer pool.
• set_logging_level Set the logging level.
• get_torch_geometric_remote_backend Use the database as the remote backend for torch_geometric.

__init__

def __init__(database_path, buffer_pool_size)

Parameters

• database_path : _kuzu.Database The path to database files

• buffer_pool_size : int The maximum size of buffer pool in bytes (Optional). Default to 80% of system memory.

resize_buffer_manager

def resize_buffer_manager(new_size)

Resize the mamimum size of buffer pool.

Parameters

• new_size : int New maximum size of buffer pool (in bytes).

set_logging_level

def set_logging_level(level)

Set the logging level.

Parameters

• level : str Logging level. One of “debug”, “info”, “err”.

get_torch_geometric_remote_backend

def get_torch_geometric_remote_backend(num_threads=None):

Use the database as the remote backend for torch_geometric.

For the interface of the remote backend, please refer to https://pytorch-geometric.readthedocs.io/en/latest/advanced/remote.html. The current implementation is read-only and does not support edge features. The IDs of the nodes are based on the internal IDs (i.e., node offsets). For the remote node IDs to be consistent with the positions in the output tensors, please ensure that no deletion has been performed on the node tables.

The remote backend can also be plugged into the data loader of torch_geometric, which is useful for mini-batch training. For example:

    loader_kuzu = NeighborLoader(
        data=(feature_store, graph_store),
        num_neighbors={('paper', 'cites', 'paper'): [12, 12, 12]},
        batch_size=LOADER_BATCH_SIZE,
        input_nodes=('paper', input_nodes),
        num_workers=4,
        filter_per_worker=False,
    )

Please note that the database instance is not fork-safe, so if more than one worker is used, filter_per_worker must be set to False.

Parameters

• num_threads : int Number of threads to use for data loading. Default to None, which means using the number of CPU cores.

Returns

• feature_store Feature store compatible with torch_geometric.
• graph_store Graph store compatible with torch_geometric.