Python session.query方法代码示例

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def _entity_corresponds_to(given, entity):
    """determine if 'given' corresponds to 'entity', in terms
    of an entity passed to Query that would match the same entity
    being referred to elsewhere in the query.

    """
    if entity.is_aliased_class:
        if given.is_aliased_class:
            if entity._base_alias is given._base_alias:
                return True
        return False
    elif given.is_aliased_class:
        if given._use_mapper_path:
            return entity in given.with_polymorphic_mappers
        else:
            return entity is given

    return entity.common_parent(given) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def create_row_processor(self, query, procs, labels):
        """Produce the "row processing" function for this :class:`.Bundle`.

        May be overridden by subclasses.

        .. seealso::

            :ref:`bundles` - includes an example of subclassing.

        """
        keyed_tuple = result_tuple(labels, [() for l in labels])

        def proc(row):
            return keyed_tuple([proc(row) for proc in procs])

        return proc 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def _entity_corresponds_to(given, entity):
    """determine if 'given' corresponds to 'entity', in terms
    of an entity passed to Query that would match the same entity
    being referred to elsewhere in the query.

    """
    if entity.is_aliased_class:
        if given.is_aliased_class:
            if entity._base_alias() is given._base_alias():
                return True
        return False
    elif given.is_aliased_class:
        if given._use_mapper_path:
            return entity in given.with_polymorphic_mappers
        else:
            return entity is given

    return entity.common_parent(given) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def join(left, right, onclause=None, isouter=False, join_to_left=None):
    """Produce an inner join between left and right clauses.

    :func:`.orm.join` is an extension to the core join interface
    provided by :func:`.sql.expression.join()`, where the
    left and right selectables may be not only core selectable
    objects such as :class:`.Table`, but also mapped classes or
    :class:`.AliasedClass` instances.   The "on" clause can
    be a SQL expression, or an attribute or string name
    referencing a configured :func:`.relationship`.

    :func:`.orm.join` is not commonly needed in modern usage,
    as its functionality is encapsulated within that of the
    :meth:`.Query.join` method, which features a
    significant amount of automation beyond :func:`.orm.join`
    by itself.  Explicit usage of :func:`.orm.join`
    with :class:`.Query` involves usage of the
    :meth:`.Query.select_from` method, as in::

        from sqlalchemy.orm import join
        session.query(User).\\
            select_from(join(User, Address, User.addresses)).\\
            filter(Address.email_address=='foo@bar.com')

    In modern SQLAlchemy the above join can be written more
    succinctly as::

        session.query(User).\\
                join(User.addresses).\\
                filter(Address.email_address=='foo@bar.com')

    See :meth:`.Query.join` for information on modern usage
    of ORM level joins.

    .. versionchanged:: 0.8.1 - the ``join_to_left`` parameter
       is no longer used, and is deprecated.

    """
    return _ORMJoin(left, right, onclause, isouter) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def with_parent(instance, prop):
    """Create filtering criterion that relates this query's primary entity
    to the given related instance, using established :func:`.relationship()`
    configuration.

    The SQL rendered is the same as that rendered when a lazy loader
    would fire off from the given parent on that attribute, meaning
    that the appropriate state is taken from the parent object in
    Python without the need to render joins to the parent table
    in the rendered statement.

    .. versionchanged:: 0.6.4
        This method accepts parent instances in all
        persistence states, including transient, persistent, and detached.
        Only the requisite primary key/foreign key attributes need to
        be populated.  Previous versions didn't work with transient
        instances.

    :param instance:
      An instance which has some :func:`.relationship`.

    :param property:
      String property name, or class-bound attribute, which indicates
      what relationship from the instance should be used to reconcile the
      parent/child relationship.

    """
    if isinstance(prop, util.string_types):
        mapper = object_mapper(instance)
        prop = getattr(mapper.class_, prop).property
    elif isinstance(prop, attributes.QueryableAttribute):
        prop = prop.property

    return prop._with_parent(instance) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def join(
        left, right, onclause=None, isouter=False,
        full=False, join_to_left=None):
    r"""Produce an inner join between left and right clauses.

    :func:`.orm.join` is an extension to the core join interface
    provided by :func:`.sql.expression.join()`, where the
    left and right selectables may be not only core selectable
    objects such as :class:`.Table`, but also mapped classes or
    :class:`.AliasedClass` instances.   The "on" clause can
    be a SQL expression, or an attribute or string name
    referencing a configured :func:`.relationship`.

    :func:`.orm.join` is not commonly needed in modern usage,
    as its functionality is encapsulated within that of the
    :meth:`.Query.join` method, which features a
    significant amount of automation beyond :func:`.orm.join`
    by itself.  Explicit usage of :func:`.orm.join`
    with :class:`.Query` involves usage of the
    :meth:`.Query.select_from` method, as in::

        from sqlalchemy.orm import join
        session.query(User).\
            select_from(join(User, Address, User.addresses)).\
            filter(Address.email_address=='foo@bar.com')

    In modern SQLAlchemy the above join can be written more
    succinctly as::

        session.query(User).\
                join(User.addresses).\
                filter(Address.email_address=='foo@bar.com')

    See :meth:`.Query.join` for information on modern usage
    of ORM level joins.

    .. versionchanged:: 0.8.1 - the ``join_to_left`` parameter
       is no longer used, and is deprecated.

    """
    return _ORMJoin(left, right, onclause, isouter, full) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def with_parent(instance, prop, from_entity=None):
    """Create filtering criterion that relates this query's primary entity
    to the given related instance, using established :func:`.relationship()`
    configuration.

    The SQL rendered is the same as that rendered when a lazy loader
    would fire off from the given parent on that attribute, meaning
    that the appropriate state is taken from the parent object in
    Python without the need to render joins to the parent table
    in the rendered statement.

    :param instance:
      An instance which has some :func:`.relationship`.

    :param property:
      String property name, or class-bound attribute, which indicates
      what relationship from the instance should be used to reconcile the
      parent/child relationship.

    :param from_entity:
      Entity in which to consider as the left side.  This defaults to the
      "zero" entity of the :class:`.Query` itself.

      .. versionadded:: 1.2

    """
    if isinstance(prop, util.string_types):
        mapper = object_mapper(instance)
        prop = getattr(mapper.class_, prop).property
    elif isinstance(prop, attributes.QueryableAttribute):
        prop = prop.property

    return prop._with_parent(instance, from_entity=from_entity) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def with_parent(instance, prop):
    """Create filtering criterion that relates this query's primary entity
    to the given related instance, using established :func:`.relationship()`
    configuration.

    The SQL rendered is the same as that rendered when a lazy loader
    would fire off from the given parent on that attribute, meaning
    that the appropriate state is taken from the parent object in
    Python without the need to render joins to the parent table
    in the rendered statement.

    .. versionchanged:: 0.6.4
        This method accepts parent instances in all
        persistence states, including transient, persistent, and detached.
        Only the requisite primary key/foreign key attributes need to
        be populated.  Previous versions didn't work with transient
        instances.

    :param instance:
      An instance which has some :func:`.relationship`.

    :param property:
      String property name, or class-bound attribute, which indicates
      what relationship from the instance should be used to reconcile the
      parent/child relationship.

    """
    if isinstance(prop, util.string_types):
        mapper = object_mapper(instance)
        prop = getattr(mapper.class_, prop).property
    elif isinstance(prop, attributes.QueryableAttribute):
        prop = prop.property

    return prop.compare(operators.eq,
                        instance,
                        value_is_parent=True) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def __init__(self, name, *exprs, **kw):
        r"""Construct a new :class:`.Bundle`.

        e.g.::

            bn = Bundle("mybundle", MyClass.x, MyClass.y)

            for row in session.query(bn).filter(
                    bn.c.x == 5).filter(bn.c.y == 4):
                print(row.mybundle.x, row.mybundle.y)

        :param name: name of the bundle.
        :param \*exprs: columns or SQL expressions comprising the bundle.
        :param single_entity=False: if True, rows for this :class:`.Bundle`
         can be returned as a "single entity" outside of any enclosing tuple
         in the same manner as a mapped entity.

        """
        self.name = self._label = name
        self.exprs = exprs = [
            coercions.expect(
                roles.ColumnsClauseRole, expr, apply_propagate_attrs=self
            )
            for expr in exprs
        ]

        self.c = self.columns = ColumnCollection(
            (getattr(col, "key", col._label), col)
            for col in [e._annotations.get("bundle", e) for e in exprs]
        )
        self.single_entity = kw.pop("single_entity", self.single_entity) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def with_parent(instance, prop, from_entity=None):
    """Create filtering criterion that relates this query's primary entity
    to the given related instance, using established
    :func:`_orm.relationship()`
    configuration.

    The SQL rendered is the same as that rendered when a lazy loader
    would fire off from the given parent on that attribute, meaning
    that the appropriate state is taken from the parent object in
    Python without the need to render joins to the parent table
    in the rendered statement.

    :param instance:
      An instance which has some :func:`_orm.relationship`.

    :param property:
      String property name, or class-bound attribute, which indicates
      what relationship from the instance should be used to reconcile the
      parent/child relationship.

    :param from_entity:
      Entity in which to consider as the left side.  This defaults to the
      "zero" entity of the :class:`_query.Query` itself.

      .. versionadded:: 1.2

    """
    if isinstance(prop, util.string_types):
        mapper = object_mapper(instance)
        prop = getattr(mapper.class_, prop).property
    elif isinstance(prop, attributes.QueryableAttribute):
        prop = prop.property

    return prop._with_parent(instance, from_entity=from_entity) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def test_engine(self):

        engine = dbutils.connect(self.json)
        self.assertIsInstance(engine, sqlalchemy.engine.base.Engine)
        table_names = ['chrom', 'hit', "orf", "external",
                       "external_sources", 'hsp', 'junctions', 'query', 'target']
        self.assertEqual(sorted(list(engine.table_names())), sorted(table_names)) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def test_content(self):

        engine = dbutils.connect(self.json)
        sessionmaker = sqlalchemy.orm.sessionmaker(bind=engine)
        session = sessionmaker()
        # Simple tests based on the static content of the dictionary
        self.assertEqual(session.query(serializers.junction.Junction).count(), 372,
                         self.json["db_settings"])
        self.assertEqual(session.query(serializers.orf.Orf).count(), 169)
        self.assertEqual(session.query(serializers.blast_serializer.Target).count(), 38909)
        self.assertEqual(session.query(serializers.blast_serializer.Query).count(), 93)
        self.assertEqual(session.query(serializers.blast_serializer.Hit).count(), 5034)
        self.assertEqual(session.query(serializers.blast_serializer.Hsp).count(), 13585)

        first_query = session.query(serializers.blast_serializer.Query).limit(1).one()
        astup = first_query.as_tuple()
        self.assertTrue(astup._fields, ("query_id", "query_name", "query_length"))
        self.assertIsInstance(astup.query_id, int)
        self.assertIsInstance(astup.query_length, int)
        self.assertIsInstance(astup.query_name, str)
        
        first_target = session.query(
            serializers.blast_serializer.Target).limit(1).one()
        astup = first_target.as_tuple()
        self.assertTrue(astup._fields, ("target_id", "target_name", "target_length"))
        self.assertIsInstance(astup.target_id, int)
        self.assertIsInstance(astup.target_length, int)
        self.assertIsInstance(astup.target_name, str) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def test_connect_to_shm(self):
        self.json["pick"]["run_options"]['shm'] = True
        shutil.copy(self.json["db_settings"]["db"], "/dev/shm/")
        self.json["db_settings"]["db"] = os.path.join("/dev/shm/",
                                                      os.path.basename(self.json["db_settings"]["db"]))
        connector = dbutils.connect(self.json)
        self.assertEqual(str(connector.url), "sqlite://")
        engine = dbutils.connect(self.json)
        sessionmaker = sqlalchemy.orm.sessionmaker(bind=engine)
        session = sessionmaker()
        first_target = session.query(serializers.blast_serializer.Target).limit(1).one()
        astup = first_target.as_tuple()
        self.assertTrue(astup._fields, ("target_id", "target_name", "target_length"))
        os.remove(os.path.join("/dev/shm/", os.path.basename(self.json["db_settings"]["db"]))) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def join(
    left, right, onclause=None, isouter=False, full=False, join_to_left=None
):
    r"""Produce an inner join between left and right clauses.

    :func:`_orm.join` is an extension to the core join interface
    provided by :func:`_expression.join()`, where the
    left and right selectables may be not only core selectable
    objects such as :class:`_schema.Table`, but also mapped classes or
    :class:`.AliasedClass` instances.   The "on" clause can
    be a SQL expression, or an attribute or string name
    referencing a configured :func:`_orm.relationship`.

    :func:`_orm.join` is not commonly needed in modern usage,
    as its functionality is encapsulated within that of the
    :meth:`_query.Query.join` method, which features a
    significant amount of automation beyond :func:`_orm.join`
    by itself.  Explicit usage of :func:`_orm.join`
    with :class:`_query.Query` involves usage of the
    :meth:`_query.Query.select_from` method, as in::

        from sqlalchemy.orm import join
        session.query(User).\
            select_from(join(User, Address, User.addresses)).\
            filter(Address.email_address=='foo@bar.com')

    In modern SQLAlchemy the above join can be written more
    succinctly as::

        session.query(User).\
                join(User.addresses).\
                filter(Address.email_address=='foo@bar.com')

    See :meth:`_query.Query.join` for information on modern usage
    of ORM level joins.

    .. deprecated:: 0.8

        the ``join_to_left`` parameter is deprecated, and will be removed
        in a future release.  The parameter has no effect.

    """
    return _ORMJoin(left, right, onclause, isouter, full) 

# 需要导入模块: from sqlalchemy.orm import session [as 别名]
# 或者: from sqlalchemy.orm.session import query [as 别名]
def polymorphic_union(table_map, typecolname,
                        aliasname='p_union', cast_nulls=True):
    """Create a ``UNION`` statement used by a polymorphic mapper.

    See  :ref:`concrete_inheritance` for an example of how
    this is used.

    :param table_map: mapping of polymorphic identities to
     :class:`.Table` objects.
    :param typecolname: string name of a "discriminator" column, which will be
     derived from the query, producing the polymorphic identity for
     each row.  If ``None``, no polymorphic discriminator is generated.
    :param aliasname: name of the :func:`~sqlalchemy.sql.expression.alias()`
     construct generated.
    :param cast_nulls: if True, non-existent columns, which are represented
     as labeled NULLs, will be passed into CAST.   This is a legacy behavior
     that is problematic on some backends such as Oracle - in which case it
     can be set to False.

    """

    colnames = util.OrderedSet()
    colnamemaps = {}
    types = {}
    for key in table_map:
        table = table_map[key]

        # mysql doesnt like selecting from a select;
        # make it an alias of the select
        if isinstance(table, sql.Select):
            table = table.alias()
            table_map[key] = table

        m = {}
        for c in table.c:
            colnames.add(c.key)
            m[c.key] = c
            types[c.key] = c.type
        colnamemaps[table] = m

    def col(name, table):
        try:
            return colnamemaps[table][name]
        except KeyError:
            if cast_nulls:
                return sql.cast(sql.null(), types[name]).label(name)
            else:
                return sql.type_coerce(sql.null(), types[name]).label(name)

    result = []
    for type, table in table_map.items():
        if typecolname is not None:
            result.append(
                    sql.select([col(name, table) for name in colnames] +
                    [sql.literal_column(sql_util._quote_ddl_expr(type)).
                            label(typecolname)],
                             from_obj=[table]))
        else:
            result.append(sql.select([col(name, table) for name in colnames],
                                     from_obj=[table]))
    return sql.union_all(*result).alias(aliasname)