Function _postfetch

lib/sqlalchemy/orm/persistence.py:1636–1739

Expire attributes in need of newly persisted database state, after an INSERT or UPDATE statement has proceeded for that state.

(
    mapper,
    uowtransaction,
    table,
    state,
    dict_,
    result,
    params,
    value_params,
    isupdate,
    returned_defaults,
)

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)