sqlalchemy.engine.result.ChunkedIteratorResult

class documentation

class ChunkedIteratorResult(IteratorResult[_TP]): (source)

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An :class:`_engine.IteratorResult` that works from an iterator-producing callable. The given ``chunks`` argument is a function that is given a number of rows to return in each chunk, or ``None`` for all rows. The function should then return an un-consumed iterator of lists, each list of the requested size. The function can be called at any time again, in which case it should continue from the same result set but adjust the chunk size as given. .. versionadded:: 1.4

Method __init__ Undocumented
Method yield_per Configure the row-fetching strategy to fetch ``num`` rows at a time.
Instance Variable chunks Undocumented
Instance Variable dynamic_yield_per Undocumented
Instance Variable iterator Undocumented
Instance Variable raw Undocumented
Method _fetchmany_impl Undocumented
Method _soft_close Undocumented
Instance Variable _metadata Undocumented
Instance Variable _source_supports_scalars Undocumented
Instance Variable _yield_per Undocumented

Inherited from IteratorResult:

Property closed Return ``True`` if this :class:`_engine.IteratorResult` has been closed
Method _fetchall_impl Undocumented
Method _fetchiter_impl Undocumented
Method _fetchone_impl Undocumented
Method _raise_hard_closed Undocumented
Method _raw_row_iterator Return a safe iterator that yields raw row data.
Instance Variable _hard_closed Undocumented
Instance Variable _soft_closed Undocumented

Inherited from Result (via IteratorResult):

Method __enter__ Undocumented
Method __exit__ Undocumented
Method __iter__ Undocumented
Method __next__ Undocumented
Method all Return all rows in a list.
Method close close this :class:`_engine.Result`.
Method columns Establish the columns that should be returned in each row.
Method fetchall A synonym for the :meth:`_engine.Result.all` method.
Method fetchmany Fetch many rows.
Method fetchone Fetch one row.
Method first Fetch the first row or ``None`` if no row is present.
Method freeze Return a callable object that will produce copies of this :class:`_engine.Result` when invoked.
Method mappings Apply a mappings filter to returned rows, returning an instance of :class:`_engine.MappingResult`.
Method merge Merge this :class:`_engine.Result` with other compatible result objects.
Method one Return exactly one row or raise an exception.
Method one_or_none Return at most one result or raise an exception.
Method partitions Iterate through sub-lists of rows of the size given.
Method scalar Fetch the first column of the first row, and close the result set.
Method scalar_one Return exactly one scalar result or raise an exception.
Method scalar_one_or_none Return exactly one scalar result or ``None``.
Method scalars Return a :class:`_engine.ScalarResult` filtering object which will return single elements rather than :class:`_row.Row` objects.
Method tuples Apply a "typed tuple" typing filter to returned rows.
Method unique Apply unique filtering to the objects returned by this :class:`_engine.Result`.
Class Variable __slots__ Undocumented
Property t Apply a "typed tuple" typing filter to returned rows.
Method _getter return a callable that will retrieve the given key from a :class:`_engine.Row`.
Method _tuple_getter return a callable that will retrieve the given keys from a :class:`_engine.Row`.
Class Variable _attributes Undocumented
Class Variable _row_logging_fn Undocumented
Instance Variable _unique_filter_state Undocumented

Inherited from _WithKeys (via IteratorResult, Result):

Method keys Return an iterable view which yields the string keys that would be represented by each :class:`_engine.Row`.

Inherited from ResultInternal (via IteratorResult, Result, _WithKeys):

Method _allrows Undocumented
Method _column_slices Undocumented
Method _iter_impl Undocumented
Method _iterator_getter Undocumented
Method _manyrow_getter Undocumented
Method _next_impl Undocumented
Method _onerow_getter Undocumented
Method _only_one_row Undocumented
Method _raw_all_rows Undocumented
Method _row_getter Undocumented
Method _unique_strategy Undocumented
Class Variable _is_cursor Undocumented
Class Variable _post_creational_filter Undocumented
Class Variable _real_result Undocumented
Instance Variable _generate_rows Undocumented

Inherited from InPlaceGenerative (via IteratorResult, Result, _WithKeys, ResultInternal):

Method _generate Undocumented
def __init__(self, cursor_metadata: ResultMetaData, chunks: Callable[[Optional[int]], Iterator[Sequence[_InterimRowType[_R]]]], source_supports_scalars: bool = False, raw: Optional[Result[Any]] = None, dynamic_yield_per: bool = False): (source)
overrides sqlalchemy.engine.result.IteratorResult.__init__

Undocumented

@_generative
def yield_per(self, num: int) -> Self: (source)
overrides sqlalchemy.engine.result.Result.yield_per

Configure the row-fetching strategy to fetch ``num`` rows at a time. This impacts the underlying behavior of the result when iterating over the result object, or otherwise making use of methods such as :meth:`_engine.Result.fetchone` that return one row at a time. Data from the underlying cursor or other data source will be buffered up to this many rows in memory, and the buffered collection will then be yielded out one row at a time or as many rows are requested. Each time the buffer clears, it will be refreshed to this many rows or as many rows remain if fewer remain. The :meth:`_engine.Result.yield_per` method is generally used in conjunction with the :paramref:`_engine.Connection.execution_options.stream_results` execution option, which will allow the database dialect in use to make use of a server side cursor, if the DBAPI supports a specific "server side cursor" mode separate from its default mode of operation. .. tip:: Consider using the :paramref:`_engine.Connection.execution_options.yield_per` execution option, which will simultaneously set :paramref:`_engine.Connection.execution_options.stream_results` to ensure the use of server side cursors, as well as automatically invoke the :meth:`_engine.Result.yield_per` method to establish a fixed row buffer size at once. The :paramref:`_engine.Connection.execution_options.yield_per` execution option is available for ORM operations, with :class:`_orm.Session`-oriented use described at :ref:`orm_queryguide_yield_per`. The Core-only version which works with :class:`_engine.Connection` is new as of SQLAlchemy 1.4.40. .. versionadded:: 1.4 :param num: number of rows to fetch each time the buffer is refilled. If set to a value below 1, fetches all rows for the next buffer. .. seealso:: :ref:`engine_stream_results` - describes Core behavior for :meth:`_engine.Result.yield_per` :ref:`orm_queryguide_yield_per` - in the :ref:`queryguide_toplevel`

chunks = (source)

Undocumented

dynamic_yield_per = (source)

Undocumented

iterator = (source)
overrides sqlalchemy.engine.result.IteratorResult.iterator

Undocumented

raw = (source)
overrides sqlalchemy.engine.result.IteratorResult.raw

Undocumented

def _fetchmany_impl(self, size: Optional[int] = None) -> List[_InterimRowType[Row[Any]]]: (source)
overrides sqlalchemy.engine.result.IteratorResult._fetchmany_impl

Undocumented

def _soft_close(self, hard: bool = False, **kw: Any): (source)
overrides sqlalchemy.engine.result.IteratorResult._soft_close

Undocumented

_metadata = (source)
overrides sqlalchemy.engine.result.IteratorResult._metadata

Undocumented

_source_supports_scalars = (source)
overrides sqlalchemy.engine.result.IteratorResult._source_supports_scalars

Undocumented

_yield_per = (source)
overrides sqlalchemy.engine.result.Result._yield_per

Undocumented