Return the current **pre-flush** change history for this attribute, via the :class:`.History` interface. This method **will** emit loader callables if the value of the attribute is unloaded. .. note:: The attribute history system tracks changes on a **p
(self)
| 1116 | return self.state.get_history(self.key, PASSIVE_NO_INITIALIZE) |
| 1117 | |
| 1118 | def load_history(self) -> History: |
| 1119 | """Return the current **pre-flush** change history for |
| 1120 | this attribute, via the :class:`.History` interface. |
| 1121 | |
| 1122 | This method **will** emit loader callables if the value of the |
| 1123 | attribute is unloaded. |
| 1124 | |
| 1125 | .. note:: |
| 1126 | |
| 1127 | The attribute history system tracks changes on a **per flush |
| 1128 | basis**. Each time the :class:`.Session` is flushed, the history |
| 1129 | of each attribute is reset to empty. The :class:`.Session` by |
| 1130 | default autoflushes each time a :class:`_query.Query` is invoked. |
| 1131 | For |
| 1132 | options on how to control this, see :ref:`session_flushing`. |
| 1133 | |
| 1134 | .. seealso:: |
| 1135 | |
| 1136 | :attr:`.AttributeState.history` |
| 1137 | |
| 1138 | :func:`.attributes.get_history` - underlying function |
| 1139 | |
| 1140 | """ |
| 1141 | return self.state.get_history(self.key, PASSIVE_OFF ^ INIT_OK) |
| 1142 | |
| 1143 | |
| 1144 | class PendingCollection: |