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diff --git a/venv/lib/python3.11/site-packages/sqlalchemy/orm/persistence.py b/venv/lib/python3.11/site-packages/sqlalchemy/orm/persistence.py
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+# orm/persistence.py
+# Copyright (C) 2005-2024 the SQLAlchemy authors and contributors
+# <see AUTHORS file>
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: https://www.opensource.org/licenses/mit-license.php
+# mypy: ignore-errors
+
+
+"""private module containing functions used to emit INSERT, UPDATE
+and DELETE statements on behalf of a :class:`_orm.Mapper` and its descending
+mappers.
+
+The functions here are called only by the unit of work functions
+in unitofwork.py.
+
+"""
+from __future__ import annotations
+
+from itertools import chain
+from itertools import groupby
+from itertools import zip_longest
+import operator
+
+from . import attributes
+from . import exc as orm_exc
+from . import loading
+from . import sync
+from .base import state_str
+from .. import exc as sa_exc
+from .. import future
+from .. import sql
+from .. import util
+from ..engine import cursor as _cursor
+from ..sql import operators
+from ..sql.elements import BooleanClauseList
+from ..sql.selectable import LABEL_STYLE_TABLENAME_PLUS_COL
+
+
+def save_obj(base_mapper, states, uowtransaction, single=False):
+    """Issue ``INSERT`` and/or ``UPDATE`` statements for a list
+    of objects.
+
+    This is called within the context of a UOWTransaction during a
+    flush operation, given a list of states to be flushed.  The
+    base mapper in an inheritance hierarchy handles the inserts/
+    updates for all descendant mappers.
+
+    """
+
+    # if batch=false, call _save_obj separately for each object
+    if not single and not base_mapper.batch:
+        for state in _sort_states(base_mapper, states):
+            save_obj(base_mapper, [state], uowtransaction, single=True)
+        return
+
+    states_to_update = []
+    states_to_insert = []
+
+    for (
+        state,
+        dict_,
+        mapper,
+        connection,
+        has_identity,
+        row_switch,
+        update_version_id,
+    ) in _organize_states_for_save(base_mapper, states, uowtransaction):
+        if has_identity or row_switch:
+            states_to_update.append(
+                (state, dict_, mapper, connection, update_version_id)
+            )
+        else:
+            states_to_insert.append((state, dict_, mapper, connection))
+
+    for table, mapper in base_mapper._sorted_tables.items():
+        if table not in mapper._pks_by_table:
+            continue
+        insert = _collect_insert_commands(table, states_to_insert)
+
+        update = _collect_update_commands(
+            uowtransaction, table, states_to_update
+        )
+
+        _emit_update_statements(
+            base_mapper,
+            uowtransaction,
+            mapper,
+            table,
+            update,
+        )
+
+        _emit_insert_statements(
+            base_mapper,
+            uowtransaction,
+            mapper,
+            table,
+            insert,
+        )
+
+    _finalize_insert_update_commands(
+        base_mapper,
+        uowtransaction,
+        chain(
+            (
+                (state, state_dict, mapper, connection, False)
+                for (state, state_dict, mapper, connection) in states_to_insert
+            ),
+            (
+                (state, state_dict, mapper, connection, True)
+                for (
+                    state,
+                    state_dict,
+                    mapper,
+                    connection,
+                    update_version_id,
+                ) in states_to_update
+            ),
+        ),
+    )
+
+
+def post_update(base_mapper, states, uowtransaction, post_update_cols):
+    """Issue UPDATE statements on behalf of a relationship() which
+    specifies post_update.
+
+    """
+
+    states_to_update = list(
+        _organize_states_for_post_update(base_mapper, states, uowtransaction)
+    )
+
+    for table, mapper in base_mapper._sorted_tables.items():
+        if table not in mapper._pks_by_table:
+            continue
+
+        update = (
+            (
+                state,
+                state_dict,
+                sub_mapper,
+                connection,
+                (
+                    mapper._get_committed_state_attr_by_column(
+                        state, state_dict, mapper.version_id_col
+                    )
+                    if mapper.version_id_col is not None
+                    else None
+                ),
+            )
+            for state, state_dict, sub_mapper, connection in states_to_update
+            if table in sub_mapper._pks_by_table
+        )
+
+        update = _collect_post_update_commands(
+            base_mapper, uowtransaction, table, update, post_update_cols
+        )
+
+        _emit_post_update_statements(
+            base_mapper,
+            uowtransaction,
+            mapper,
+            table,
+            update,
+        )
+
+
+def delete_obj(base_mapper, states, uowtransaction):
+    """Issue ``DELETE`` statements for a list of objects.
+
+    This is called within the context of a UOWTransaction during a
+    flush operation.
+
+    """
+
+    states_to_delete = list(
+        _organize_states_for_delete(base_mapper, states, uowtransaction)
+    )
+
+    table_to_mapper = base_mapper._sorted_tables
+
+    for table in reversed(list(table_to_mapper.keys())):
+        mapper = table_to_mapper[table]
+        if table not in mapper._pks_by_table:
+            continue
+        elif mapper.inherits and mapper.passive_deletes:
+            continue
+
+        delete = _collect_delete_commands(
+            base_mapper, uowtransaction, table, states_to_delete
+        )
+
+        _emit_delete_statements(
+            base_mapper,
+            uowtransaction,
+            mapper,
+            table,
+            delete,
+        )
+
+    for (
+        state,
+        state_dict,
+        mapper,
+        connection,
+        update_version_id,
+    ) in states_to_delete:
+        mapper.dispatch.after_delete(mapper, connection, state)
+
+
+def _organize_states_for_save(base_mapper, states, uowtransaction):
+    """Make an initial pass across a set of states for INSERT or
+    UPDATE.
+
+    This includes splitting out into distinct lists for
+    each, calling before_insert/before_update, obtaining
+    key information for each state including its dictionary,
+    mapper, the connection to use for the execution per state,
+    and the identity flag.
+
+    """
+
+    for state, dict_, mapper, connection in _connections_for_states(
+        base_mapper, uowtransaction, states
+    ):
+        has_identity = bool(state.key)
+
+        instance_key = state.key or mapper._identity_key_from_state(state)
+
+        row_switch = update_version_id = None
+
+        # call before_XXX extensions
+        if not has_identity:
+            mapper.dispatch.before_insert(mapper, connection, state)
+        else:
+            mapper.dispatch.before_update(mapper, connection, state)
+
+        if mapper._validate_polymorphic_identity:
+            mapper._validate_polymorphic_identity(mapper, state, dict_)
+
+        # detect if we have a "pending" instance (i.e. has
+        # no instance_key attached to it), and another instance
+        # with the same identity key already exists as persistent.
+        # convert to an UPDATE if so.
+        if (
+            not has_identity
+            and instance_key in uowtransaction.session.identity_map
+        ):
+            instance = uowtransaction.session.identity_map[instance_key]
+            existing = attributes.instance_state(instance)
+
+            if not uowtransaction.was_already_deleted(existing):
+                if not uowtransaction.is_deleted(existing):
+                    util.warn(
+                        "New instance %s with identity key %s conflicts "
+                        "with persistent instance %s"
+                        % (state_str(state), instance_key, state_str(existing))
+                    )
+                else:
+                    base_mapper._log_debug(
+                        "detected row switch for identity %s.  "
+                        "will update %s, remove %s from "
+                        "transaction",
+                        instance_key,
+                        state_str(state),
+                        state_str(existing),
+                    )
+
+                    # remove the "delete" flag from the existing element
+                    uowtransaction.remove_state_actions(existing)
+                    row_switch = existing
+
+        if (has_identity or row_switch) and mapper.version_id_col is not None:
+            update_version_id = mapper._get_committed_state_attr_by_column(
+                row_switch if row_switch else state,
+                row_switch.dict if row_switch else dict_,
+                mapper.version_id_col,
+            )
+
+        yield (
+            state,
+            dict_,
+            mapper,
+            connection,
+            has_identity,
+            row_switch,
+            update_version_id,
+        )
+
+
+def _organize_states_for_post_update(base_mapper, states, uowtransaction):
+    """Make an initial pass across a set of states for UPDATE
+    corresponding to post_update.
+
+    This includes obtaining key information for each state
+    including its dictionary, mapper, the connection to use for
+    the execution per state.
+
+    """
+    return _connections_for_states(base_mapper, uowtransaction, states)
+
+
+def _organize_states_for_delete(base_mapper, states, uowtransaction):
+    """Make an initial pass across a set of states for DELETE.
+
+    This includes calling out before_delete and obtaining
+    key information for each state including its dictionary,
+    mapper, the connection to use for the execution per state.
+
+    """
+    for state, dict_, mapper, connection in _connections_for_states(
+        base_mapper, uowtransaction, states
+    ):
+        mapper.dispatch.before_delete(mapper, connection, state)
+
+        if mapper.version_id_col is not None:
+            update_version_id = mapper._get_committed_state_attr_by_column(
+                state, dict_, mapper.version_id_col
+            )
+        else:
+            update_version_id = None
+
+        yield (state, dict_, mapper, connection, update_version_id)
+
+
+def _collect_insert_commands(
+    table,
+    states_to_insert,
+    *,
+    bulk=False,
+    return_defaults=False,
+    render_nulls=False,
+    include_bulk_keys=(),
+):
+    """Identify sets of values to use in INSERT statements for a
+    list of states.
+
+    """
+    for state, state_dict, mapper, connection in states_to_insert:
+        if table not in mapper._pks_by_table:
+            continue
+
+        params = {}
+        value_params = {}
+
+        propkey_to_col = mapper._propkey_to_col[table]
+
+        eval_none = mapper._insert_cols_evaluating_none[table]
+
+        for propkey in set(propkey_to_col).intersection(state_dict):
+            value = state_dict[propkey]
+            col = propkey_to_col[propkey]
+            if value is None and col not in eval_none and not render_nulls:
+                continue
+            elif not bulk and (
+                hasattr(value, "__clause_element__")
+                or isinstance(value, sql.ClauseElement)
+            ):
+                value_params[col] = (
+                    value.__clause_element__()
+                    if hasattr(value, "__clause_element__")
+                    else value
+                )
+            else:
+                params[col.key] = value
+
+        if not bulk:
+            # for all the columns that have no default and we don't have
+            # a value and where "None" is not a special value, add
+            # explicit None to the INSERT.   This is a legacy behavior
+            # which might be worth removing, as it should not be necessary
+            # and also produces confusion, given that "missing" and None
+            # now have distinct meanings
+            for colkey in (
+                mapper._insert_cols_as_none[table]
+                .difference(params)
+                .difference([c.key for c in value_params])
+            ):
+                params[colkey] = None
+
+        if not bulk or return_defaults:
+            # params are in terms of Column key objects, so
+            # compare to pk_keys_by_table
+            has_all_pks = mapper._pk_keys_by_table[table].issubset(params)
+
+            if mapper.base_mapper._prefer_eager_defaults(
+                connection.dialect, table
+            ):
+                has_all_defaults = mapper._server_default_col_keys[
+                    table
+                ].issubset(params)
+            else:
+                has_all_defaults = True
+        else:
+            has_all_defaults = has_all_pks = True
+
+        if (
+            mapper.version_id_generator is not False
+            and mapper.version_id_col is not None
+            and mapper.version_id_col in mapper._cols_by_table[table]
+        ):
+            params[mapper.version_id_col.key] = mapper.version_id_generator(
+                None
+            )
+
+        if bulk:
+            if mapper._set_polymorphic_identity:
+                params.setdefault(
+                    mapper._polymorphic_attr_key, mapper.polymorphic_identity
+                )
+
+            if include_bulk_keys:
+                params.update((k, state_dict[k]) for k in include_bulk_keys)
+
+        yield (
+            state,
+            state_dict,
+            params,
+            mapper,
+            connection,
+            value_params,
+            has_all_pks,
+            has_all_defaults,
+        )
+
+
+def _collect_update_commands(
+    uowtransaction,
+    table,
+    states_to_update,
+    *,
+    bulk=False,
+    use_orm_update_stmt=None,
+    include_bulk_keys=(),
+):
+    """Identify sets of values to use in UPDATE statements for a
+    list of states.
+
+    This function works intricately with the history system
+    to determine exactly what values should be updated
+    as well as how the row should be matched within an UPDATE
+    statement.  Includes some tricky scenarios where the primary
+    key of an object might have been changed.
+
+    """
+
+    for (
+        state,
+        state_dict,
+        mapper,
+        connection,
+        update_version_id,
+    ) in states_to_update:
+        if table not in mapper._pks_by_table:
+            continue
+
+        pks = mapper._pks_by_table[table]
+
+        if use_orm_update_stmt is not None:
+            # TODO: ordered values, etc
+            value_params = use_orm_update_stmt._values
+        else:
+            value_params = {}
+
+        propkey_to_col = mapper._propkey_to_col[table]
+
+        if bulk:
+            # keys here are mapped attribute keys, so
+            # look at mapper attribute keys for pk
+            params = {
+                propkey_to_col[propkey].key: state_dict[propkey]
+                for propkey in set(propkey_to_col)
+                .intersection(state_dict)
+                .difference(mapper._pk_attr_keys_by_table[table])
+            }
+            has_all_defaults = True
+        else:
+            params = {}
+            for propkey in set(propkey_to_col).intersection(
+                state.committed_state
+            ):
+                value = state_dict[propkey]
+                col = propkey_to_col[propkey]
+
+                if hasattr(value, "__clause_element__") or isinstance(
+                    value, sql.ClauseElement
+                ):
+                    value_params[col] = (
+                        value.__clause_element__()
+                        if hasattr(value, "__clause_element__")
+                        else value
+                    )
+                # guard against values that generate non-__nonzero__
+                # objects for __eq__()
+                elif (
+                    state.manager[propkey].impl.is_equal(
+                        value, state.committed_state[propkey]
+                    )
+                    is not True
+                ):
+                    params[col.key] = value
+
+            if mapper.base_mapper.eager_defaults is True:
+                has_all_defaults = (
+                    mapper._server_onupdate_default_col_keys[table]
+                ).issubset(params)
+            else:
+                has_all_defaults = True
+
+        if (
+            update_version_id is not None
+            and mapper.version_id_col in mapper._cols_by_table[table]
+        ):
+            if not bulk and not (params or value_params):
+                # HACK: check for history in other tables, in case the
+                # history is only in a different table than the one
+                # where the version_id_col is.  This logic was lost
+                # from 0.9 -> 1.0.0 and restored in 1.0.6.
+                for prop in mapper._columntoproperty.values():
+                    history = state.manager[prop.key].impl.get_history(
+                        state, state_dict, attributes.PASSIVE_NO_INITIALIZE
+                    )
+                    if history.added:
+                        break
+                else:
+                    # no net change, break
+                    continue
+
+            col = mapper.version_id_col
+            no_params = not params and not value_params
+            params[col._label] = update_version_id
+
+            if (
+                bulk or col.key not in params
+            ) and mapper.version_id_generator is not False:
+                val = mapper.version_id_generator(update_version_id)
+                params[col.key] = val
+            elif mapper.version_id_generator is False and no_params:
+                # no version id generator, no values set on the table,
+                # and version id wasn't manually incremented.
+                # set version id to itself so we get an UPDATE
+                # statement
+                params[col.key] = update_version_id
+
+        elif not (params or value_params):
+            continue
+
+        has_all_pks = True
+        expect_pk_cascaded = False
+        if bulk:
+            # keys here are mapped attribute keys, so
+            # look at mapper attribute keys for pk
+            pk_params = {
+                propkey_to_col[propkey]._label: state_dict.get(propkey)
+                for propkey in set(propkey_to_col).intersection(
+                    mapper._pk_attr_keys_by_table[table]
+                )
+            }
+            if util.NONE_SET.intersection(pk_params.values()):
+                raise sa_exc.InvalidRequestError(
+                    f"No primary key value supplied for column(s) "
+                    f"""{
+                        ', '.join(
+                            str(c) for c in pks if pk_params[c._label] is None
+                        )
+                    }; """
+                    "per-row ORM Bulk UPDATE by Primary Key requires that "
+                    "records contain primary key values",
+                    code="bupq",
+                )
+
+        else:
+            pk_params = {}
+            for col in pks:
+                propkey = mapper._columntoproperty[col].key
+
+                history = state.manager[propkey].impl.get_history(
+                    state, state_dict, attributes.PASSIVE_OFF
+                )
+
+                if history.added:
+                    if (
+                        not history.deleted
+                        or ("pk_cascaded", state, col)
+                        in uowtransaction.attributes
+                    ):
+                        expect_pk_cascaded = True
+                        pk_params[col._label] = history.added[0]
+                        params.pop(col.key, None)
+                    else:
+                        # else, use the old value to locate the row
+                        pk_params[col._label] = history.deleted[0]
+                        if col in value_params:
+                            has_all_pks = False
+                else:
+                    pk_params[col._label] = history.unchanged[0]
+                if pk_params[col._label] is None:
+                    raise orm_exc.FlushError(
+                        "Can't update table %s using NULL for primary "
+                        "key value on column %s" % (table, col)
+                    )
+
+        if include_bulk_keys:
+            params.update((k, state_dict[k]) for k in include_bulk_keys)
+
+        if params or value_params:
+            params.update(pk_params)
+            yield (
+                state,
+                state_dict,
+                params,
+                mapper,
+                connection,
+                value_params,
+                has_all_defaults,
+                has_all_pks,
+            )
+        elif expect_pk_cascaded:
+            # no UPDATE occurs on this table, but we expect that CASCADE rules
+            # have changed the primary key of the row; propagate this event to
+            # other columns that expect to have been modified. this normally
+            # occurs after the UPDATE is emitted however we invoke it here
+            # explicitly in the absence of our invoking an UPDATE
+            for m, equated_pairs in mapper._table_to_equated[table]:
+                sync.populate(
+                    state,
+                    m,
+                    state,
+                    m,
+                    equated_pairs,
+                    uowtransaction,
+                    mapper.passive_updates,
+                )
+
+
+def _collect_post_update_commands(
+    base_mapper, uowtransaction, table, states_to_update, post_update_cols
+):
+    """Identify sets of values to use in UPDATE statements for a
+    list of states within a post_update operation.
+
+    """
+
+    for (
+        state,
+        state_dict,
+        mapper,
+        connection,
+        update_version_id,
+    ) in states_to_update:
+        # assert table in mapper._pks_by_table
+
+        pks = mapper._pks_by_table[table]
+        params = {}
+        hasdata = False
+
+        for col in mapper._cols_by_table[table]:
+            if col in pks:
+                params[col._label] = mapper._get_state_attr_by_column(
+                    state, state_dict, col, passive=attributes.PASSIVE_OFF
+                )
+
+            elif col in post_update_cols or col.onupdate is not None:
+                prop = mapper._columntoproperty[col]
+                history = state.manager[prop.key].impl.get_history(
+                    state, state_dict, attributes.PASSIVE_NO_INITIALIZE
+                )
+                if history.added:
+                    value = history.added[0]
+                    params[col.key] = value
+                    hasdata = True
+        if hasdata:
+            if (
+                update_version_id is not None
+                and mapper.version_id_col in mapper._cols_by_table[table]
+            ):
+                col = mapper.version_id_col
+                params[col._label] = update_version_id
+
+                if (
+                    bool(state.key)
+                    and col.key not in params
+                    and mapper.version_id_generator is not False
+                ):
+                    val = mapper.version_id_generator(update_version_id)
+                    params[col.key] = val
+            yield state, state_dict, mapper, connection, params
+
+
+def _collect_delete_commands(
+    base_mapper, uowtransaction, table, states_to_delete
+):
+    """Identify values to use in DELETE statements for a list of
+    states to be deleted."""
+
+    for (
+        state,
+        state_dict,
+        mapper,
+        connection,
+        update_version_id,
+    ) in states_to_delete:
+        if table not in mapper._pks_by_table:
+            continue
+
+        params = {}
+        for col in mapper._pks_by_table[table]:
+            params[col.key] = value = (
+                mapper._get_committed_state_attr_by_column(
+                    state, state_dict, col
+                )
+            )
+            if value is None:
+                raise orm_exc.FlushError(
+                    "Can't delete from table %s "
+                    "using NULL for primary "
+                    "key value on column %s" % (table, col)
+                )
+
+        if (
+            update_version_id is not None
+            and mapper.version_id_col in mapper._cols_by_table[table]
+        ):
+            params[mapper.version_id_col.key] = update_version_id
+        yield params, connection
+
+
+def _emit_update_statements(
+    base_mapper,
+    uowtransaction,
+    mapper,
+    table,
+    update,
+    *,
+    bookkeeping=True,
+    use_orm_update_stmt=None,
+    enable_check_rowcount=True,
+):
+    """Emit UPDATE statements corresponding to value lists collected
+    by _collect_update_commands()."""
+
+    needs_version_id = (
+        mapper.version_id_col is not None
+        and mapper.version_id_col in mapper._cols_by_table[table]
+    )
+
+    execution_options = {"compiled_cache": base_mapper._compiled_cache}
+
+    def update_stmt(existing_stmt=None):
+        clauses = BooleanClauseList._construct_raw(operators.and_)
+
+        for col in mapper._pks_by_table[table]:
+            clauses._append_inplace(
+                col == sql.bindparam(col._label, type_=col.type)
+            )
+
+        if needs_version_id:
+            clauses._append_inplace(
+                mapper.version_id_col
+                == sql.bindparam(
+                    mapper.version_id_col._label,
+                    type_=mapper.version_id_col.type,
+                )
+            )
+
+        if existing_stmt is not None:
+            stmt = existing_stmt.where(clauses)
+        else:
+            stmt = table.update().where(clauses)
+        return stmt
+
+    if use_orm_update_stmt is not None:
+        cached_stmt = update_stmt(use_orm_update_stmt)
+
+    else:
+        cached_stmt = base_mapper._memo(("update", table), update_stmt)
+
+    for (
+        (connection, paramkeys, hasvalue, has_all_defaults, has_all_pks),
+        records,
+    ) in groupby(
+        update,
+        lambda rec: (
+            rec[4],  # connection
+            set(rec[2]),  # set of parameter keys
+            bool(rec[5]),  # whether or not we have "value" parameters
+            rec[6],  # has_all_defaults
+            rec[7],  # has all pks
+        ),
+    ):
+        rows = 0
+        records = list(records)
+
+        statement = cached_stmt
+
+        if use_orm_update_stmt is not None:
+            statement = statement._annotate(
+                {
+                    "_emit_update_table": table,
+                    "_emit_update_mapper": mapper,
+                }
+            )
+
+        return_defaults = False
+
+        if not has_all_pks:
+            statement = statement.return_defaults(*mapper._pks_by_table[table])
+            return_defaults = True
+
+        if (
+            bookkeeping
+            and not has_all_defaults
+            and mapper.base_mapper.eager_defaults is True
+            # change as of #8889 - if RETURNING is not going to be used anyway,
+            # (applies to MySQL, MariaDB which lack UPDATE RETURNING) ensure
+            # we can do an executemany UPDATE which is more efficient
+            and table.implicit_returning
+            and connection.dialect.update_returning
+        ):
+            statement = statement.return_defaults(
+                *mapper._server_onupdate_default_cols[table]
+            )
+            return_defaults = True
+
+        if mapper._version_id_has_server_side_value:
+            statement = statement.return_defaults(mapper.version_id_col)
+            return_defaults = True
+
+        assert_singlerow = connection.dialect.supports_sane_rowcount
+
+        assert_multirow = (
+            assert_singlerow
+            and connection.dialect.supports_sane_multi_rowcount
+        )
+
+        # change as of #8889 - if RETURNING is not going to be used anyway,
+        # (applies to MySQL, MariaDB which lack UPDATE RETURNING) ensure
+        # we can do an executemany UPDATE which is more efficient
+        allow_executemany = not return_defaults and not needs_version_id
+
+        if hasvalue:
+            for (
+                state,
+                state_dict,
+                params,
+                mapper,
+                connection,
+                value_params,
+                has_all_defaults,
+                has_all_pks,
+            ) in records:
+                c = connection.execute(
+                    statement.values(value_params),
+                    params,
+                    execution_options=execution_options,
+                )
+                if bookkeeping:
+                    _postfetch(
+                        mapper,
+                        uowtransaction,
+                        table,
+                        state,
+                        state_dict,
+                        c,
+                        c.context.compiled_parameters[0],
+                        value_params,
+                        True,
+                        c.returned_defaults,
+                    )
+                rows += c.rowcount
+                check_rowcount = enable_check_rowcount and assert_singlerow
+        else:
+            if not allow_executemany:
+                check_rowcount = enable_check_rowcount and assert_singlerow
+                for (
+                    state,
+                    state_dict,
+                    params,
+                    mapper,
+                    connection,
+                    value_params,
+                    has_all_defaults,
+                    has_all_pks,
+                ) in records:
+                    c = connection.execute(
+                        statement, params, execution_options=execution_options
+                    )
+
+                    # TODO: why with bookkeeping=False?
+                    if bookkeeping:
+                        _postfetch(
+                            mapper,
+                            uowtransaction,
+                            table,
+                            state,
+                            state_dict,
+                            c,
+                            c.context.compiled_parameters[0],
+                            value_params,
+                            True,
+                            c.returned_defaults,
+                        )
+                    rows += c.rowcount
+            else:
+                multiparams = [rec[2] for rec in records]
+
+                check_rowcount = enable_check_rowcount and (
+                    assert_multirow
+                    or (assert_singlerow and len(multiparams) == 1)
+                )
+
+                c = connection.execute(
+                    statement, multiparams, execution_options=execution_options
+                )
+
+                rows += c.rowcount
+
+                for (
+                    state,
+                    state_dict,
+                    params,
+                    mapper,
+                    connection,
+                    value_params,
+                    has_all_defaults,
+                    has_all_pks,
+                ) in records:
+                    if bookkeeping:
+                        _postfetch(
+                            mapper,
+                            uowtransaction,
+                            table,
+                            state,
+                            state_dict,
+                            c,
+                            c.context.compiled_parameters[0],
+                            value_params,
+                            True,
+                            (
+                                c.returned_defaults
+                                if not c.context.executemany
+                                else None
+                            ),
+                        )
+
+        if check_rowcount:
+            if rows != len(records):
+                raise orm_exc.StaleDataError(
+                    "UPDATE statement on table '%s' expected to "
+                    "update %d row(s); %d were matched."
+                    % (table.description, len(records), rows)
+                )
+
+        elif needs_version_id:
+            util.warn(
+                "Dialect %s does not support updated rowcount "
+                "- versioning cannot be verified."
+                % c.dialect.dialect_description
+            )
+
+
+def _emit_insert_statements(
+    base_mapper,
+    uowtransaction,
+    mapper,
+    table,
+    insert,
+    *,
+    bookkeeping=True,
+    use_orm_insert_stmt=None,
+    execution_options=None,
+):
+    """Emit INSERT statements corresponding to value lists collected
+    by _collect_insert_commands()."""
+
+    if use_orm_insert_stmt is not None:
+        cached_stmt = use_orm_insert_stmt
+        exec_opt = util.EMPTY_DICT
+
+        # if a user query with RETURNING was passed, we definitely need
+        # to use RETURNING.
+        returning_is_required_anyway = bool(use_orm_insert_stmt._returning)
+        deterministic_results_reqd = (
+            returning_is_required_anyway
+            and use_orm_insert_stmt._sort_by_parameter_order
+        ) or bookkeeping
+    else:
+        returning_is_required_anyway = False
+        deterministic_results_reqd = bookkeeping
+        cached_stmt = base_mapper._memo(("insert", table), table.insert)
+        exec_opt = {"compiled_cache": base_mapper._compiled_cache}
+
+    if execution_options:
+        execution_options = util.EMPTY_DICT.merge_with(
+            exec_opt, execution_options
+        )
+    else:
+        execution_options = exec_opt
+
+    return_result = None
+
+    for (
+        (connection, _, hasvalue, has_all_pks, has_all_defaults),
+        records,
+    ) in groupby(
+        insert,
+        lambda rec: (
+            rec[4],  # connection
+            set(rec[2]),  # parameter keys
+            bool(rec[5]),  # whether we have "value" parameters
+            rec[6],
+            rec[7],
+        ),
+    ):
+        statement = cached_stmt
+
+        if use_orm_insert_stmt is not None:
+            statement = statement._annotate(
+                {
+                    "_emit_insert_table": table,
+                    "_emit_insert_mapper": mapper,
+                }
+            )
+
+        if (
+            (
+                not bookkeeping
+                or (
+                    has_all_defaults
+                    or not base_mapper._prefer_eager_defaults(
+                        connection.dialect, table
+                    )
+                    or not table.implicit_returning
+                    or not connection.dialect.insert_returning
+                )
+            )
+            and not returning_is_required_anyway
+            and has_all_pks
+            and not hasvalue
+        ):
+            # the "we don't need newly generated values back" section.
+            # here we have all the PKs, all the defaults or we don't want
+            # to fetch them, or the dialect doesn't support RETURNING at all
+            # so we have to post-fetch / use lastrowid anyway.
+            records = list(records)
+            multiparams = [rec[2] for rec in records]
+
+            result = connection.execute(
+                statement, multiparams, execution_options=execution_options
+            )
+            if bookkeeping:
+                for (
+                    (
+                        state,
+                        state_dict,
+                        params,
+                        mapper_rec,
+                        conn,
+                        value_params,
+                        has_all_pks,
+                        has_all_defaults,
+                    ),
+                    last_inserted_params,
+                ) in zip(records, result.context.compiled_parameters):
+                    if state:
+                        _postfetch(
+                            mapper_rec,
+                            uowtransaction,
+                            table,
+                            state,
+                            state_dict,
+                            result,
+                            last_inserted_params,
+                            value_params,
+                            False,
+                            (
+                                result.returned_defaults
+                                if not result.context.executemany
+                                else None
+                            ),
+                        )
+                    else:
+                        _postfetch_bulk_save(mapper_rec, state_dict, table)
+
+        else:
+            # here, we need defaults and/or pk values back or we otherwise
+            # know that we are using RETURNING in any case
+
+            records = list(records)
+
+            if returning_is_required_anyway or (
+                table.implicit_returning and not hasvalue and len(records) > 1
+            ):
+                if (
+                    deterministic_results_reqd
+                    and connection.dialect.insert_executemany_returning_sort_by_parameter_order  # noqa: E501
+                ) or (
+                    not deterministic_results_reqd
+                    and connection.dialect.insert_executemany_returning
+                ):
+                    do_executemany = True
+                elif returning_is_required_anyway:
+                    if deterministic_results_reqd:
+                        dt = " with RETURNING and sort by parameter order"
+                    else:
+                        dt = " with RETURNING"
+                    raise sa_exc.InvalidRequestError(
+                        f"Can't use explicit RETURNING for bulk INSERT "
+                        f"operation with "
+                        f"{connection.dialect.dialect_description} backend; "
+                        f"executemany{dt} is not enabled for this dialect."
+                    )
+                else:
+                    do_executemany = False
+            else:
+                do_executemany = False
+
+            if use_orm_insert_stmt is None:
+                if (
+                    not has_all_defaults
+                    and base_mapper._prefer_eager_defaults(
+                        connection.dialect, table
+                    )
+                ):
+                    statement = statement.return_defaults(
+                        *mapper._server_default_cols[table],
+                        sort_by_parameter_order=bookkeeping,
+                    )
+
+            if mapper.version_id_col is not None:
+                statement = statement.return_defaults(
+                    mapper.version_id_col,
+                    sort_by_parameter_order=bookkeeping,
+                )
+            elif do_executemany:
+                statement = statement.return_defaults(
+                    *table.primary_key, sort_by_parameter_order=bookkeeping
+                )
+
+            if do_executemany:
+                multiparams = [rec[2] for rec in records]
+
+                result = connection.execute(
+                    statement, multiparams, execution_options=execution_options
+                )
+
+                if use_orm_insert_stmt is not None:
+                    if return_result is None:
+                        return_result = result
+                    else:
+                        return_result = return_result.splice_vertically(result)
+
+                if bookkeeping:
+                    for (
+                        (
+                            state,
+                            state_dict,
+                            params,
+                            mapper_rec,
+                            conn,
+                            value_params,
+                            has_all_pks,
+                            has_all_defaults,
+                        ),
+                        last_inserted_params,
+                        inserted_primary_key,
+                        returned_defaults,
+                    ) in zip_longest(
+                        records,
+                        result.context.compiled_parameters,
+                        result.inserted_primary_key_rows,
+                        result.returned_defaults_rows or (),
+                    ):
+                        if inserted_primary_key is None:
+                            # this is a real problem and means that we didn't
+                            # get back as many PK rows.  we can't continue
+                            # since this indicates PK rows were missing, which
+                            # means we likely mis-populated records starting
+                            # at that point with incorrectly matched PK
+                            # values.
+                            raise orm_exc.FlushError(
+                                "Multi-row INSERT statement for %s did not "
+                                "produce "
+                                "the correct number of INSERTed rows for "
+                                "RETURNING.  Ensure there are no triggers or "
+                                "special driver issues preventing INSERT from "
+                                "functioning properly." % mapper_rec
+                            )
+
+                        for pk, col in zip(
+                            inserted_primary_key,
+                            mapper._pks_by_table[table],
+                        ):
+                            prop = mapper_rec._columntoproperty[col]
+                            if state_dict.get(prop.key) is None:
+                                state_dict[prop.key] = pk
+
+                        if state:
+                            _postfetch(
+                                mapper_rec,
+                                uowtransaction,
+                                table,
+                                state,
+                                state_dict,
+                                result,
+                                last_inserted_params,
+                                value_params,
+                                False,
+                                returned_defaults,
+                            )
+                        else:
+                            _postfetch_bulk_save(mapper_rec, state_dict, table)
+            else:
+                assert not returning_is_required_anyway
+
+                for (
+                    state,
+                    state_dict,
+                    params,
+                    mapper_rec,
+                    connection,
+                    value_params,
+                    has_all_pks,
+                    has_all_defaults,
+                ) in records:
+                    if value_params:
+                        result = connection.execute(
+                            statement.values(value_params),
+                            params,
+                            execution_options=execution_options,
+                        )
+                    else:
+                        result = connection.execute(
+                            statement,
+                            params,
+                            execution_options=execution_options,
+                        )
+
+                    primary_key = result.inserted_primary_key
+                    if primary_key is None:
+                        raise orm_exc.FlushError(
+                            "Single-row INSERT statement for %s "
+                            "did not produce a "
+                            "new primary key result "
+                            "being invoked.  Ensure there are no triggers or "
+                            "special driver issues preventing INSERT from "
+                            "functioning properly." % (mapper_rec,)
+                        )
+                    for pk, col in zip(
+                        primary_key, mapper._pks_by_table[table]
+                    ):
+                        prop = mapper_rec._columntoproperty[col]
+                        if (
+                            col in value_params
+                            or state_dict.get(prop.key) is None
+                        ):
+                            state_dict[prop.key] = pk
+                    if bookkeeping:
+                        if state:
+                            _postfetch(
+                                mapper_rec,
+                                uowtransaction,
+                                table,
+                                state,
+                                state_dict,
+                                result,
+                                result.context.compiled_parameters[0],
+                                value_params,
+                                False,
+                                (
+                                    result.returned_defaults
+                                    if not result.context.executemany
+                                    else None
+                                ),
+                            )
+                        else:
+                            _postfetch_bulk_save(mapper_rec, state_dict, table)
+
+    if use_orm_insert_stmt is not None:
+        if return_result is None:
+            return _cursor.null_dml_result()
+        else:
+            return return_result
+
+
+def _emit_post_update_statements(
+    base_mapper, uowtransaction, mapper, table, update
+):
+    """Emit UPDATE statements corresponding to value lists collected
+    by _collect_post_update_commands()."""
+
+    execution_options = {"compiled_cache": base_mapper._compiled_cache}
+
+    needs_version_id = (
+        mapper.version_id_col is not None
+        and mapper.version_id_col in mapper._cols_by_table[table]
+    )
+
+    def update_stmt():
+        clauses = BooleanClauseList._construct_raw(operators.and_)
+
+        for col in mapper._pks_by_table[table]:
+            clauses._append_inplace(
+                col == sql.bindparam(col._label, type_=col.type)
+            )
+
+        if needs_version_id:
+            clauses._append_inplace(
+                mapper.version_id_col
+                == sql.bindparam(
+                    mapper.version_id_col._label,
+                    type_=mapper.version_id_col.type,
+                )
+            )
+
+        stmt = table.update().where(clauses)
+
+        return stmt
+
+    statement = base_mapper._memo(("post_update", table), update_stmt)
+
+    if mapper._version_id_has_server_side_value:
+        statement = statement.return_defaults(mapper.version_id_col)
+
+    # execute each UPDATE in the order according to the original
+    # list of states to guarantee row access order, but
+    # also group them into common (connection, cols) sets
+    # to support executemany().
+    for key, records in groupby(
+        update,
+        lambda rec: (rec[3], set(rec[4])),  # connection  # parameter keys
+    ):
+        rows = 0
+
+        records = list(records)
+        connection = key[0]
+
+        assert_singlerow = connection.dialect.supports_sane_rowcount
+        assert_multirow = (
+            assert_singlerow
+            and connection.dialect.supports_sane_multi_rowcount
+        )
+        allow_executemany = not needs_version_id or assert_multirow
+
+        if not allow_executemany:
+            check_rowcount = assert_singlerow
+            for state, state_dict, mapper_rec, connection, params in records:
+                c = connection.execute(
+                    statement, params, execution_options=execution_options
+                )
+
+                _postfetch_post_update(
+                    mapper_rec,
+                    uowtransaction,
+                    table,
+                    state,
+                    state_dict,
+                    c,
+                    c.context.compiled_parameters[0],
+                )
+                rows += c.rowcount
+        else:
+            multiparams = [
+                params
+                for state, state_dict, mapper_rec, conn, params in records
+            ]
+
+            check_rowcount = assert_multirow or (
+                assert_singlerow and len(multiparams) == 1
+            )
+
+            c = connection.execute(
+                statement, multiparams, execution_options=execution_options
+            )
+
+            rows += c.rowcount
+            for state, state_dict, mapper_rec, connection, params in records:
+                _postfetch_post_update(
+                    mapper_rec,
+                    uowtransaction,
+                    table,
+                    state,
+                    state_dict,
+                    c,
+                    c.context.compiled_parameters[0],
+                )
+
+        if check_rowcount:
+            if rows != len(records):
+                raise orm_exc.StaleDataError(
+                    "UPDATE statement on table '%s' expected to "
+                    "update %d row(s); %d were matched."
+                    % (table.description, len(records), rows)
+                )
+
+        elif needs_version_id:
+            util.warn(
+                "Dialect %s does not support updated rowcount "
+                "- versioning cannot be verified."
+                % c.dialect.dialect_description
+            )
+
+
+def _emit_delete_statements(
+    base_mapper, uowtransaction, mapper, table, delete
+):
+    """Emit DELETE statements corresponding to value lists collected
+    by _collect_delete_commands()."""
+
+    need_version_id = (
+        mapper.version_id_col is not None
+        and mapper.version_id_col in mapper._cols_by_table[table]
+    )
+
+    def delete_stmt():
+        clauses = BooleanClauseList._construct_raw(operators.and_)
+
+        for col in mapper._pks_by_table[table]:
+            clauses._append_inplace(
+                col == sql.bindparam(col.key, type_=col.type)
+            )
+
+        if need_version_id:
+            clauses._append_inplace(
+                mapper.version_id_col
+                == sql.bindparam(
+                    mapper.version_id_col.key, type_=mapper.version_id_col.type
+                )
+            )
+
+        return table.delete().where(clauses)
+
+    statement = base_mapper._memo(("delete", table), delete_stmt)
+    for connection, recs in groupby(delete, lambda rec: rec[1]):  # connection
+        del_objects = [params for params, connection in recs]
+
+        execution_options = {"compiled_cache": base_mapper._compiled_cache}
+        expected = len(del_objects)
+        rows_matched = -1
+        only_warn = False
+
+        if (
+            need_version_id
+            and not connection.dialect.supports_sane_multi_rowcount
+        ):
+            if connection.dialect.supports_sane_rowcount:
+                rows_matched = 0
+                # execute deletes individually so that versioned
+                # rows can be verified
+                for params in del_objects:
+                    c = connection.execute(
+                        statement, params, execution_options=execution_options
+                    )
+                    rows_matched += c.rowcount
+            else:
+                util.warn(
+                    "Dialect %s does not support deleted rowcount "
+                    "- versioning cannot be verified."
+                    % connection.dialect.dialect_description
+                )
+                connection.execute(
+                    statement, del_objects, execution_options=execution_options
+                )
+        else:
+            c = connection.execute(
+                statement, del_objects, execution_options=execution_options
+            )
+
+            if not need_version_id:
+                only_warn = True
+
+            rows_matched = c.rowcount
+
+        if (
+            base_mapper.confirm_deleted_rows
+            and rows_matched > -1
+            and expected != rows_matched
+            and (
+                connection.dialect.supports_sane_multi_rowcount
+                or len(del_objects) == 1
+            )
+        ):
+            # TODO: why does this "only warn" if versioning is turned off,
+            # whereas the UPDATE raises?
+            if only_warn:
+                util.warn(
+                    "DELETE statement on table '%s' expected to "
+                    "delete %d row(s); %d were matched.  Please set "
+                    "confirm_deleted_rows=False within the mapper "
+                    "configuration to prevent this warning."
+                    % (table.description, expected, rows_matched)
+                )
+            else:
+                raise orm_exc.StaleDataError(
+                    "DELETE statement on table '%s' expected to "
+                    "delete %d row(s); %d were matched.  Please set "
+                    "confirm_deleted_rows=False within the mapper "
+                    "configuration to prevent this warning."
+                    % (table.description, expected, rows_matched)
+                )
+
+
+def _finalize_insert_update_commands(base_mapper, uowtransaction, states):
+    """finalize state on states that have been inserted or updated,
+    including calling after_insert/after_update events.
+
+    """
+    for state, state_dict, mapper, connection, has_identity in states:
+        if mapper._readonly_props:
+            readonly = state.unmodified_intersection(
+                [
+                    p.key
+                    for p in mapper._readonly_props
+                    if (
+                        p.expire_on_flush
+                        and (not p.deferred or p.key in state.dict)
+                    )
+                    or (
+                        not p.expire_on_flush
+                        and not p.deferred
+                        and p.key not in state.dict
+                    )
+                ]
+            )
+            if readonly:
+                state._expire_attributes(state.dict, readonly)
+
+        # if eager_defaults option is enabled, load
+        # all expired cols.  Else if we have a version_id_col, make sure
+        # it isn't expired.
+        toload_now = []
+
+        # this is specifically to emit a second SELECT for eager_defaults,
+        # so only if it's set to True, not "auto"
+        if base_mapper.eager_defaults is True:
+            toload_now.extend(
+                state._unloaded_non_object.intersection(
+                    mapper._server_default_plus_onupdate_propkeys
+                )
+            )
+
+        if (
+            mapper.version_id_col is not None
+            and mapper.version_id_generator is False
+        ):
+            if mapper._version_id_prop.key in state.unloaded:
+                toload_now.extend([mapper._version_id_prop.key])
+
+        if toload_now:
+            state.key = base_mapper._identity_key_from_state(state)
+            stmt = future.select(mapper).set_label_style(
+                LABEL_STYLE_TABLENAME_PLUS_COL
+            )
+            loading.load_on_ident(
+                uowtransaction.session,
+                stmt,
+                state.key,
+                refresh_state=state,
+                only_load_props=toload_now,
+            )
+
+        # call after_XXX extensions
+        if not has_identity:
+            mapper.dispatch.after_insert(mapper, connection, state)
+        else:
+            mapper.dispatch.after_update(mapper, connection, state)
+
+        if (
+            mapper.version_id_generator is False
+            and mapper.version_id_col is not None
+        ):
+            if state_dict[mapper._version_id_prop.key] is None:
+                raise orm_exc.FlushError(
+                    "Instance does not contain a non-NULL version value"
+                )
+
+
+def _postfetch_post_update(
+    mapper, uowtransaction, table, state, dict_, result, params
+):
+    needs_version_id = (
+        mapper.version_id_col is not None
+        and mapper.version_id_col in mapper._cols_by_table[table]
+    )
+
+    if not uowtransaction.is_deleted(state):
+        # post updating after a regular INSERT or UPDATE, do a full postfetch
+        prefetch_cols = result.context.compiled.prefetch
+        postfetch_cols = result.context.compiled.postfetch
+    elif needs_version_id:
+        # post updating before a DELETE with a version_id_col, need to
+        # postfetch just version_id_col
+        prefetch_cols = postfetch_cols = ()
+    else:
+        # post updating before a DELETE without a version_id_col,
+        # don't need to postfetch
+        return
+
+    if needs_version_id:
+        prefetch_cols = list(prefetch_cols) + [mapper.version_id_col]
+
+    refresh_flush = bool(mapper.class_manager.dispatch.refresh_flush)
+    if refresh_flush:
+        load_evt_attrs = []
+
+    for c in prefetch_cols:
+        if c.key in params and c in mapper._columntoproperty:
+            dict_[mapper._columntoproperty[c].key] = params[c.key]
+            if refresh_flush:
+                load_evt_attrs.append(mapper._columntoproperty[c].key)
+
+    if refresh_flush and load_evt_attrs:
+        mapper.class_manager.dispatch.refresh_flush(
+            state, uowtransaction, load_evt_attrs
+        )
+
+    if postfetch_cols:
+        state._expire_attributes(
+            state.dict,
+            [
+                mapper._columntoproperty[c].key
+                for c in postfetch_cols
+                if c in mapper._columntoproperty
+            ],
+        )
+
+
+def _postfetch(
+    mapper,
+    uowtransaction,
+    table,
+    state,
+    dict_,
+    result,
+    params,
+    value_params,
+    isupdate,
+    returned_defaults,
+):
+    """Expire attributes in need of newly persisted database state,
+    after an INSERT or UPDATE statement has proceeded for that
+    state."""
+
+    prefetch_cols = result.context.compiled.prefetch
+    postfetch_cols = result.context.compiled.postfetch
+    returning_cols = result.context.compiled.effective_returning
+
+    if (
+        mapper.version_id_col is not None
+        and mapper.version_id_col in mapper._cols_by_table[table]
+    ):
+        prefetch_cols = list(prefetch_cols) + [mapper.version_id_col]
+
+    refresh_flush = bool(mapper.class_manager.dispatch.refresh_flush)
+    if refresh_flush:
+        load_evt_attrs = []
+
+    if returning_cols:
+        row = returned_defaults
+        if row is not None:
+            for row_value, col in zip(row, returning_cols):
+                # pk cols returned from insert are handled
+                # distinctly, don't step on the values here
+                if col.primary_key and result.context.isinsert:
+                    continue
+
+                # note that columns can be in the "return defaults" that are
+                # not mapped to this mapper, typically because they are
+                # "excluded", which can be specified directly or also occurs
+                # when using declarative w/ single table inheritance
+                prop = mapper._columntoproperty.get(col)
+                if prop:
+                    dict_[prop.key] = row_value
+                    if refresh_flush:
+                        load_evt_attrs.append(prop.key)
+
+    for c in prefetch_cols:
+        if c.key in params and c in mapper._columntoproperty:
+            pkey = mapper._columntoproperty[c].key
+
+            # set prefetched value in dict and also pop from committed_state,
+            # since this is new database state that replaces whatever might
+            # have previously been fetched (see #10800).  this is essentially a
+            # shorthand version of set_committed_value(), which could also be
+            # used here directly (with more overhead)
+            dict_[pkey] = params[c.key]
+            state.committed_state.pop(pkey, None)
+
+            if refresh_flush:
+                load_evt_attrs.append(pkey)
+
+    if refresh_flush and load_evt_attrs:
+        mapper.class_manager.dispatch.refresh_flush(
+            state, uowtransaction, load_evt_attrs
+        )
+
+    if isupdate and value_params:
+        # explicitly suit the use case specified by
+        # [ticket:3801], PK SQL expressions for UPDATE on non-RETURNING
+        # database which are set to themselves in order to do a version bump.
+        postfetch_cols.extend(
+            [
+                col
+                for col in value_params
+                if col.primary_key and col not in returning_cols
+            ]
+        )
+
+    if postfetch_cols:
+        state._expire_attributes(
+            state.dict,
+            [
+                mapper._columntoproperty[c].key
+                for c in postfetch_cols
+                if c in mapper._columntoproperty
+            ],
+        )
+
+    # synchronize newly inserted ids from one table to the next
+    # TODO: this still goes a little too often.  would be nice to
+    # have definitive list of "columns that changed" here
+    for m, equated_pairs in mapper._table_to_equated[table]:
+        sync.populate(
+            state,
+            m,
+            state,
+            m,
+            equated_pairs,
+            uowtransaction,
+            mapper.passive_updates,
+        )
+
+
+def _postfetch_bulk_save(mapper, dict_, table):
+    for m, equated_pairs in mapper._table_to_equated[table]:
+        sync.bulk_populate_inherit_keys(dict_, m, equated_pairs)
+
+
+def _connections_for_states(base_mapper, uowtransaction, states):
+    """Return an iterator of (state, state.dict, mapper, connection).
+
+    The states are sorted according to _sort_states, then paired
+    with the connection they should be using for the given
+    unit of work transaction.
+
+    """
+    # if session has a connection callable,
+    # organize individual states with the connection
+    # to use for update
+    if uowtransaction.session.connection_callable:
+        connection_callable = uowtransaction.session.connection_callable
+    else:
+        connection = uowtransaction.transaction.connection(base_mapper)
+        connection_callable = None
+
+    for state in _sort_states(base_mapper, states):
+        if connection_callable:
+            connection = connection_callable(base_mapper, state.obj())
+
+        mapper = state.manager.mapper
+
+        yield state, state.dict, mapper, connection
+
+
+def _sort_states(mapper, states):
+    pending = set(states)
+    persistent = {s for s in pending if s.key is not None}
+    pending.difference_update(persistent)
+
+    try:
+        persistent_sorted = sorted(
+            persistent, key=mapper._persistent_sortkey_fn
+        )
+    except TypeError as err:
+        raise sa_exc.InvalidRequestError(
+            "Could not sort objects by primary key; primary key "
+            "values must be sortable in Python (was: %s)" % err
+        ) from err
+    return (
+        sorted(pending, key=operator.attrgetter("insert_order"))
+        + persistent_sorted
+    )