aiida.orm.implementation.sql package¶

This module is for subclasses of the generic backend entities that only apply to SQL backends

All SQL backends with an ORM should subclass from the classes in this module

class aiida.orm.implementation.sql.SqlBackend[source]¶

Bases: typing.Generic, aiida.orm.implementation.backends.Backend

A class for SQL based backends. Assumptions are that:

there is an ORM
that it is possible to convert from ORM model instances to backend instances
that psycopg2 is used as the engine

if any of these assumptions do not fit then just implement a backend from aiida.orm.implementation.Backend

__abstractmethods__ = frozenset(['transaction', 'logs', 'migrate', 'execute_raw', 'computers', 'query_manager', 'comments', 'cursor', 'authinfos', 'groups', 'get_backend_entity', 'query', 'nodes', 'users'])¶

__args__ = None¶

__dict__ = dict_proxy({'_abc_cache': <_weakrefset.WeakSet object>, '__module__': 'aiida.orm.implementation.sql.backends', '__orig_bases__': (typing.Generic[~ModelType], <class 'aiida.orm.implementation.backends.Backend'>), 'execute_prepared_statement': <function execute_prepared_statement>, u'__origin__': None, 'execute_raw': <function execute_raw>, '__abstractmethods__': frozenset(['transaction', 'logs', 'migrate', 'execute_raw', 'computers', 'query_manager', 'comments', 'cursor', 'authinfos', 'groups', 'get_backend_entity', 'query', 'nodes', 'users']), '_abc_generic_negative_cache_version': 40, '__tree_hash__': 5926332592025, 'cursor': <function cursor>, '_abc_registry': <_weakrefset.WeakSet object>, '__args__': None, '_gorg': aiida.orm.implementation.sql.backends.SqlBackend, 'get_backend_entity': <function get_backend_entity>, '__dict__': <attribute '__dict__' of 'SqlBackend' objects>, '__next_in_mro__': <class 'aiida.orm.implementation.backends.Backend'>, '__parameters__': (~ModelType,), '_abc_generic_negative_cache': <_weakrefset.WeakSet object>, '__weakref__': <attribute '__weakref__' of 'SqlBackend' objects>, '__doc__': '\n A class for SQL based backends. Assumptions are that:\n * there is an ORM\n * that it is possible to convert from ORM model instances to backend instances\n * that psycopg2 is used as the engine\n\n if any of these assumptions do not fit then just implement a backend from :class:`aiida.orm.implementation.Backend`\n ', u'__extra__': None})¶

__extra__ = None¶

__module__ = 'aiida.orm.implementation.sql.backends'¶

__next_in_mro__¶: alias of aiida.orm.implementation.backends.Backend

__orig_bases__ = (typing.Generic[~ModelType], <class 'aiida.orm.implementation.backends.Backend'>)¶

__origin__ = None¶

__parameters__ = (~ModelType,)¶

__tree_hash__ = 5926332592025¶

__weakref__¶: list of weak references to the object (if defined)

_abc_cache = <_weakrefset.WeakSet object>¶

_abc_generic_negative_cache = <_weakrefset.WeakSet object>¶

_abc_generic_negative_cache_version = 40¶

_abc_registry = <_weakrefset.WeakSet object>¶

_gorg¶: alias of SqlBackend

cursor()[source]¶

Return a psycopg cursor. This method should be used as a context manager i.e.:

with backend.cursor():
    # Do stuff

Returns:	a psycopg cursor
Return type:	`psycopg2.extensions.cursor`

execute_prepared_statement(sql, parameters)[source]¶

Execute an SQL statement with optional prepared statements.

Parameters:	sql – the SQL statement string parameters – dictionary to use to populate the prepared statement

execute_raw(query)[source]¶

Execute a raw SQL statement and return the result.

Parameters:	query – a string containing a raw SQL statement
Returns:	the result of the query

get_backend_entity(model)[source]¶

Return the backend entity that corresponds to the given Model instance

Parameters:	model – the ORM model instance to promote to a backend instance
Returns:	the backend entity corresponding to the given model
Return type:	`aiida.orm.implementation.BackendEntity`

Submodules¶

Generic backend related objects

class aiida.orm.implementation.sql.backends.SqlBackend[source]¶