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docs/connections-and-transactions.md

@@ -34,6 +34,12 @@ available.
 This means you have to be careful when using `iterate` to not open another connection via `connection` (except you set `force_rollback` to False before opening the connection).
 Otherwise it will deadlock.
 
+Example for `force_rollback`:
+
+```python
+{!> ../docs_src/connections/force_rollback.py !}
+```
+
 ## Transactions
 
 Transactions are lazily initialized. You dont't need a connected database to create them via `database.transaction()`.
@@ -49,15 +55,6 @@ Whenever the transaction is activated, a connected database is required.
 A second way to get a transaction is via the `Connection`. It has also a `transaction()` method.
 
 
-### Auto-rollback (`force_rollback`)
-
-Transactions support an keyword parameter named `force_rollback` which default to `False`.
-When set to `True` at the end of the transaction a rollback is tried.
-This means all changes are undone.
-
-This is a simpler variant of `force_rollback` of the database object.
-
-
 ### The three ways to use a transaction
 
 #### Via the async context manager protocol
@@ -87,6 +84,18 @@ For a lower-level transaction API:
 {!> ../docs_src/transactions/manually.py !}
 ```
 
+### Auto-rollback (`force_rollback`)
+
+Transactions support an keyword parameter named `force_rollback` which default to `False`.
+When set to `True` at the end of the transaction a rollback is tried.
+This means all changes are undone.
+
+This is a simpler variant of `force_rollback` of the database object.
+```python
+{!> ../docs_src/transactions/force_rollback_transaction.py !}
+```
+
+
 ### Isolation level
 
 The state of a transaction is liked to the connection used in the currently executing async task.

docs_src/connections/force_rollback.py

@@ -0,0 +1,15 @@
+from databasez import Database
+
+database = Database("sqlite:///foo.sqlite", force_rollback=True)
+
+
+def test_foo():
+    async with database:
+        ...
+        # do the tests
+    # and now everything is rolled back
+
+    async with database:
+        ...
+        # do the tests
+    # and now everything is rolled back again

docs_src/transactions/force_rollback_transaction.py

@@ -0,0 +1,15 @@
+from databasez import Database
+
+database = Database("sqlite:///foo.sqlite")
+
+
+def test_foo():
+    async with database:
+        await database.execute(...)
+
+        async with database.transaction(force_rollback=True):
+            # this is rolled back
+            await database.execute(...)
+            async with database.transaction(force_rollback=False):
+                ...
+                # this is saved