sage.database.postgres_backends package

Subpackages

Submodules

sage.database.postgres_backends.connector module

class sage.database.postgres_backends.connector.PostgresConnector(table_name: str, dbname: str, user: str, password: str, host: str = '', port: int = 5432, fetch_size: int = 500)

Bases: sage.database.db_connector.DatabaseConnector

A PostgresConnector search for RDF triples in a PostgreSQL database.

Args:

  • table_name: Name of the SQL table containing RDF data.

  • dbname: the database name.

  • user: user name used to authenticate.

  • password: password used to authenticate.

  • host: database host address (defaults to UNIX socket if not provided).

  • port: connection port number (defaults to 5432 if not provided).

  • fetch_size: The number of SQL rows/RDF triples to fetch per batch (defaults to 500).

abort_transaction() → None

Abort any ongoing transaction

close() → None

Close the database connection

commit_transaction() → None

Commit any ongoing transaction

open() → None

Open the connection to the PostgreSQL database and initialize histograms.

start_transaction() → None

Start a PostgreSQL transaction

sage.database.postgres_backends.transaction_manager module

class sage.database.postgres_backends.transaction_manager.TransactionManager(dbname: str, user: str, password: str, host: str = '', port: int = 5432)

Bases: object

A TransactionManager handles transactions for a (MVCC-)PostgreSQL connector.

Args:

  • dbname: the database name.

  • user: user name used to authenticate.

  • password: password used to authenticate.

  • host: database host address (defaults to UNIX socket if not provided).

  • port: connection port number (defaults to 5432 if not provided).

abort() → bool

Abort an ongoing transaction

close_all() → None

Close all connections & rollback any ongoing transactions

close_connection() → None

Close the connection for a given processs

commit() → bool

Commit an ongoing transaction

get_connection()

Get the connection of the current processs

is_open() → bool

Returns True if the current process has an open connection to the DB

open_connection() → None

Open a new connection for the given process

start_transaction()

Starts a new transaction

Module contents