1 files changed, 31 insertions, 0 deletions
diff --git a/lib/sqlalchemy/orm/exc.py b/lib/sqlalchemy/orm/exc.py
new file mode 100644
index 000000000..2d1d2b108
--- /dev/null
+++ b/lib/sqlalchemy/orm/exc.py
@@ -0,0 +1,31 @@
+# exc.py - ORM exceptions
+# Copyright (C) the SQLAlchemy authors and contributors
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""SQLAlchemy ORM exceptions."""
+
+import sqlalchemy.exceptions as sa_exc
+
+
+class ConcurrentModificationError(sa_exc.SQLAlchemyError):
+    """Rows have been modified outside of the unit of work."""
+
+
+class FlushError(sa_exc.SQLAlchemyError):
+    """A invalid condition was detected during flush()."""
+
+
+class ObjectDeletedError(sa_exc.InvalidRequestError):
+    """An refresh() operation failed to re-retrieve an object's row."""
+
+
+class UnmappedColumnError(sa_exc.InvalidRequestError):
+    """Mapping operation was requested on an unknown column."""
+
+
+# Legacy compat until 0.6.
+sa_exc.ConcurrentModificationError = ConcurrentModificationError
+sa_exc.FlushError = FlushError
+sa_exc.UnmappedColumnError