Transactions And Sessions¶

Ormdantic exposes two transaction layers:

Direct Transaction¶

async with db.transaction():
    await db[Flavor].insert(Flavor(id="vanilla", name="Vanilla"))

The context manager commits on success and rolls back on error.

The transaction API accepts backend-aware options such as isolation level, read-only mode, and deferrable behavior where supported.

async with db.transaction(isolation="serializable", read_only=False):
    ...

Unsupported options are rejected instead of silently ignored.

async with db.transaction():
    async with db.savepoint("before_optional_work"):
        await db[Flavor].insert(Flavor(id="trial", name="Trial"))

If the savepoint block raises, Ormdantic rolls back to the savepoint and releases it according to backend support.

Sessions stage object changes:

async with db.session() as session:
    session.add(Flavor(id="vanilla", name="Vanilla"))

A session begins a transaction, tracks new/dirty/deleted models, uses an identity map, flushes before commit, and rolls back on context errors.

Method	Purpose
`add(model)`	Stage a new model and reachable relationship objects.
`mark_dirty(model)`	Stage an existing model for update.
`delete(model)`	Stage a model and loaded child collections for deletion.
`merge(model)`	Merge detached state into the identity map.
`flush()`	Write staged changes without closing the transaction.
`commit()`	Flush and commit.
`rollback()`	Discard staged changes and roll back.
`refresh(model)`	Reload by primary key.
`get(Model, pk)`	Return cached or loaded model.