Create CNAME

docs/CNAME

@@ -0,0 +1 @@
+fastapi-toolsets.d3vyce.fr

docs/module/crud.md

@@ -36,7 +36,7 @@ class UserCrud(AsyncCrud[User]):
     default_load_options = [selectinload(User.role)]
 ```
 
-Subclassing [`AsyncCrud`](../reference/crud.md#fastapi_toolsets.crud.factory.AsyncCrud) directly is the preferred style when you need to add custom methods or when the configuration is complex enough to benefit from a named class body. 
+Subclassing [`AsyncCrud`](../reference/crud.md#fastapi_toolsets.crud.factory.AsyncCrud) directly is the preferred style when you need to add custom methods or when the configuration is complex enough to benefit from a named class body.
 
 ### Adding custom methods
 
@@ -474,7 +474,7 @@ The distinct values are returned in the `filter_attributes` field of [`Paginated
   "filter_attributes": {
     "status": ["active", "inactive"],
     "country": ["DE", "FR", "US"],
-    "name": ["admin", "editor", "viewer"]
+    "role__name": ["admin", "editor", "viewer"]
   }
 }
 ```
@@ -482,7 +482,7 @@ The distinct values are returned in the `filter_attributes` field of [`Paginated
 Use `filter_by` to pass the client's chosen filter values directly — no need to build SQLAlchemy conditions by hand. Any unknown key raises [`InvalidFacetFilterError`](../reference/exceptions.md#fastapi_toolsets.exceptions.exceptions.InvalidFacetFilterError).
 
 !!! info "The keys in `filter_by` are the same keys the client received in `filter_attributes`."
-    Keys are normally the terminal `column.key` (e.g. `"name"` for `Role.name`). When two facet fields share the same column key (e.g. `(Build.project, Project.name)` and `(Build.os, Os.name)`), the relationship name is prepended automatically: `"project__name"` and `"os__name"`.
+    Keys use `__` as a separator for the full relationship chain. A direct column `User.status` produces `"status"`. A relationship tuple `(User.role, Role.name)` produces `"role__name"`. A deeper chain `(User.role, Role.permission, Permission.name)` produces `"role__permission__name"`.
 
 `filter_by` and `filters` can be combined — both are applied with AND logic.
 
@@ -515,9 +515,9 @@ async def list_users(
 Both single-value and multi-value query parameters work:
 
 ```
-GET /users?status=active              → filter_by={"status": ["active"]}
+GET /users?status=active                      → filter_by={"status": ["active"]}
-GET /users?status=active&country=FR   → filter_by={"status": ["active"], "country": ["FR"]}
+GET /users?status=active&country=FR           → filter_by={"status": ["active"], "country": ["FR"]}
-GET /users?role=admin&role=editor     → filter_by={"role": ["admin", "editor"]}  (IN clause)
+GET /users?role__name=admin&role__name=editor → filter_by={"role__name": ["admin", "editor"]}  (IN clause)
 ```
 
 ## Sorting

docs/module/fixtures.md

@@ -38,18 +38,20 @@ By context with [`load_fixtures_by_context`](../reference/fixtures.md#fastapi_to
 from fastapi_toolsets.fixtures import load_fixtures_by_context
 
 async with db_context() as session:
-    await load_fixtures_by_context(session=session, registry=fixtures, context=Context.TESTING)
+    await load_fixtures_by_context(session, fixtures, Context.TESTING)
 ```
 
-Directly with [`load_fixtures`](../reference/fixtures.md#fastapi_toolsets.fixtures.utils.load_fixtures):
+Directly by name with [`load_fixtures`](../reference/fixtures.md#fastapi_toolsets.fixtures.utils.load_fixtures):
 
 ```python
 from fastapi_toolsets.fixtures import load_fixtures
 
 async with db_context() as session:
-    await load_fixtures(session=session, registry=fixtures)
+    await load_fixtures(session, fixtures, "roles", "test_users")
 ```
 
+Both functions return a `dict[str, list[...]]` mapping each fixture name to the list of loaded instances.
+
 ## Contexts
 
 [`Context`](../reference/fixtures.md#fastapi_toolsets.fixtures.enum.Context) is an enum with predefined values:
@@ -58,10 +60,60 @@ async with db_context() as session:
 |---------|-------------|
 | `Context.BASE` | Core data required in all environments |
 | `Context.TESTING` | Data only loaded during tests |
+| `Context.DEVELOPMENT` | Data only loaded in development |
 | `Context.PRODUCTION` | Data only loaded in production |
 
 A fixture with no `contexts` defined takes `Context.BASE` by default.
 
+### Custom contexts
+
+Plain strings and any `Enum` subclass are accepted wherever a `Context` enum is expected.
+
+```python
+from enum import Enum
+
+class AppContext(str, Enum):
+    STAGING = "staging"
+    DEMO = "demo"
+
+@fixtures.register(contexts=[AppContext.STAGING])
+def staging_data():
+    return [Config(key="feature_x", enabled=True)]
+
+await load_fixtures_by_context(session, fixtures, AppContext.STAGING)
+```
+
+### Default context for a registry
+
+Pass `contexts` to `FixtureRegistry` to set a default for all fixtures registered in it:
+
+```python
+testing_registry = FixtureRegistry(contexts=[Context.TESTING])
+
+@testing_registry.register          # implicitly contexts=[Context.TESTING]
+def test_orders():
+    return [Order(id=1, total=99)]
+```
+
+### Same fixture name, multiple context variants
+
+The same fixture name may be registered under different (non-overlapping) context sets. When multiple contexts are loaded together, all matching variants are merged:
+
+```python
+@fixtures.register(contexts=[Context.BASE])
+def users():
+    return [User(id=1, username="admin")]
+
+@fixtures.register(contexts=[Context.TESTING])
+def users():
+    return [User(id=2, username="tester")]
+
+# loads both admin and tester
+await load_fixtures_by_context(session, fixtures, Context.BASE, Context.TESTING)
+```
+
+Registering two variants with overlapping context sets raises `ValueError`.
+
 ## Load strategies
 
 [`LoadStrategy`](../reference/fixtures.md#fastapi_toolsets.fixtures.enum.LoadStrategy) controls how the fixture loader handles rows that already exist:
@@ -69,20 +121,44 @@ A fixture with no `contexts` defined takes `Context.BASE` by default.
 | Strategy | Description |
 |----------|-------------|
 | `LoadStrategy.INSERT` | Insert only, fail on duplicates |
-| `LoadStrategy.UPSERT` | Insert or update on conflict |
+| `LoadStrategy.MERGE` | Insert or update on conflict (default) |
-| `LoadStrategy.SKIP` | Skip rows that already exist |
+| `LoadStrategy.SKIP_EXISTING` | Skip rows that already exist |
+
+```python
+await load_fixtures_by_context(
+    session, fixtures, Context.BASE, strategy=LoadStrategy.SKIP_EXISTING
+)
+```
 
 ## Merging registries
 
-Split fixtures definitions across modules and merge them:
+Split fixture definitions across modules and merge them:
 
 ```python
 from myapp.fixtures.dev import dev_fixtures
 from myapp.fixtures.prod import prod_fixtures
 
-fixtures = fixturesRegistry()
+fixtures = FixtureRegistry()
 fixtures.include_registry(registry=dev_fixtures)
 fixtures.include_registry(registry=prod_fixtures)
+```
+
+Fixtures with the same name are allowed as long as their context sets do not overlap. Conflicting contexts raise `ValueError`.
+
+## Looking up fixture instances
+
+[`get_obj_by_attr`](../reference/fixtures.md#fastapi_toolsets.fixtures.utils.get_obj_by_attr) retrieves a specific instance from a fixture function by attribute value — useful when building cross-fixture `depends_on` relationships:
+
+```python
+from fastapi_toolsets.fixtures import get_obj_by_attr
+
+@fixtures.register(depends_on=["roles"])
+def users():
+    admin_role = get_obj_by_attr(roles, "name", "admin")
+    return [User(id=1, username="alice", role_id=admin_role.id)]
+```
+
+Raises `StopIteration` if no matching instance is found.
 
 ## Pytest integration
 
@@ -111,7 +187,6 @@ async def test_user_can_login(fixture_users: list[User], fixture_roles: list[Rol
     ...
 ```
 
-
 The load order is resolved automatically from the `depends_on` declarations in your registry. Each generated fixture receives `db_session` as a dependency and returns the list of loaded model instances.
 
 ## CLI integration

src/fastapi_toolsets/crud/search.py

@@ -2,7 +2,6 @@
 
 import asyncio
 import functools
-from collections import Counter
 from collections.abc import Sequence
 from dataclasses import dataclass, replace
 from typing import TYPE_CHECKING, Any, Literal
@@ -151,7 +150,7 @@ def build_search_filters(
 
 
 def facet_keys(facet_fields: Sequence[FacetFieldType]) -> list[str]:
-    """Return a key for each facet field, disambiguating duplicate column keys.
+    """Return a key for each facet field.
 
     Args:
         facet_fields: Sequence of facet fields — either direct columns or
@@ -160,22 +159,12 @@ def facet_keys(facet_fields: Sequence[FacetFieldType]) -> list[str]:
     Returns:
         A list of string keys, one per facet field, in the same order.
     """
-    raw: list[tuple[str, str | None]] = []
+    keys: list[str] = []
     for field in facet_fields:
         if isinstance(field, tuple):
-            rel = field[-2]
+            keys.append("__".join(el.key for el in field))
-            column = field[-1]
-            raw.append((column.key, rel.key))
         else:
-            raw.append((field.key, None))
+            keys.append(field.key)
-
-    counts = Counter(col_key for col_key, _ in raw)
-    keys: list[str] = []
-    for col_key, rel_key in raw:
-        if counts[col_key] > 1 and rel_key is not None:
-            keys.append(f"{rel_key}__{col_key}")
-        else:
-            keys.append(col_key)
     return keys
 
 

src/fastapi_toolsets/fixtures/registry.py

@@ -2,6 +2,7 @@
 
 from collections.abc import Callable, Sequence
 from dataclasses import dataclass, field
+from enum import Enum
 from typing import Any, cast
 
 from sqlalchemy.orm import DeclarativeBase
@@ -12,6 +13,13 @@ from .enum import Context
 logger = get_logger()
 
 
+def _normalize_contexts(
+    contexts: list[str | Enum] | tuple[str | Enum, ...],
+) -> list[str]:
+    """Convert a sequence of any Enum subclass and/or plain strings to a list of strings."""
+    return [c.value if isinstance(c, Enum) else c for c in contexts]
+
+
 @dataclass
 class Fixture:
     """A fixture definition with metadata."""
@@ -50,26 +58,51 @@ class FixtureRegistry:
                 Post(id=1, title="Test", user_id=1),
             ]
         ```
+
+    Fixtures with the same name may be registered for **different** contexts.
+    When multiple contexts are loaded together, their instances are merged:
+
+        ```python
+        @fixtures.register(contexts=[Context.BASE])
+        def users():
+            return [User(id=1, username="admin")]
+
+        @fixtures.register(contexts=[Context.TESTING])
+        def users():
+            return [User(id=2, username="tester")]
+        # load_fixtures_by_context(..., Context.BASE, Context.TESTING)
+        # → loads both User(admin) and User(tester) under the "users" name
+        ```
     """
 
     def __init__(
         self,
-        contexts: list[str | Context] | None = None,
+        contexts: list[str | Enum] | None = None,
     ) -> None:
-        self._fixtures: dict[str, Fixture] = {}
+        self._fixtures: dict[str, list[Fixture]] = {}
         self._default_contexts: list[str] | None = (
-            [c.value if isinstance(c, Context) else c for c in contexts]
+            _normalize_contexts(contexts) if contexts else None
-            if contexts
-            else None
         )
 
+    def _validate_no_context_overlap(self, name: str, new_contexts: list[str]) -> None:
+        """Raise ``ValueError`` if any existing variant for *name* overlaps."""
+        existing_variants = self._fixtures.get(name, [])
+        new_set = set(new_contexts)
+        for variant in existing_variants:
+            if set(variant.contexts) & new_set:
+                raise ValueError(
+                    f"Fixture '{name}' already exists in the current registry "
+                    f"with overlapping contexts. Use distinct context sets for "
+                    f"each variant of the same fixture name."
+                )
+
     def register(
         self,
         func: Callable[[], Sequence[DeclarativeBase]] | None = None,
         *,
         name: str | None = None,
         depends_on: list[str] | None = None,
-        contexts: list[str | Context] | None = None,
+        contexts: list[str | Enum] | None = None,
     ) -> Callable[..., Any]:
         """Register a fixture function.
 
@@ -79,7 +112,8 @@ class FixtureRegistry:
             func: Fixture function returning list of model instances
             name: Fixture name (defaults to function name)
             depends_on: List of fixture names this depends on
-            contexts: List of contexts this fixture belongs to
+            contexts: List of contexts this fixture belongs to.  Both
+                :class:`Context` enum values and plain strings are accepted.
 
         Example:
             ```python
@@ -90,7 +124,6 @@ class FixtureRegistry:
             @fixtures.register(depends_on=["roles"], contexts=[Context.TESTING])
             def test_users():
                 return [User(id=1, username="test", role_id=1)]
-            ```
         """
 
         def decorator(
@@ -98,19 +131,20 @@ class FixtureRegistry:
         ) -> Callable[[], Sequence[DeclarativeBase]]:
             fixture_name = name or cast(Any, fn).__name__
             if contexts is not None:
-                fixture_contexts = [
+                fixture_contexts = _normalize_contexts(contexts)
-                    c.value if isinstance(c, Context) else c for c in contexts
-                ]
             elif self._default_contexts is not None:
                 fixture_contexts = self._default_contexts
             else:
                 fixture_contexts = [Context.BASE.value]
 
-            self._fixtures[fixture_name] = Fixture(
+            self._validate_no_context_overlap(fixture_name, fixture_contexts)
-                name=fixture_name,
+            self._fixtures.setdefault(fixture_name, []).append(
-                func=fn,
+                Fixture(
-                depends_on=depends_on or [],
+                    name=fixture_name,
-                contexts=fixture_contexts,
+                    func=fn,
+                    depends_on=depends_on or [],
+                    contexts=fixture_contexts,
+                )
             )
             return fn
 
@@ -121,11 +155,14 @@ class FixtureRegistry:
     def include_registry(self, registry: "FixtureRegistry") -> None:
         """Include another `FixtureRegistry` in the same current `FixtureRegistry`.
 
+        Fixtures with the same name are allowed as long as their context sets
+        do not overlap.  Conflicting contexts raise :class:`ValueError`.
+
         Args:
             registry: The `FixtureRegistry` to include
 
         Raises:
-            ValueError: If a fixture name already exists in the current registry
+            ValueError: If a fixture name already exists with overlapping contexts
 
         Example:
             ```python
@@ -139,31 +176,73 @@ class FixtureRegistry:
             registry.include_registry(registry=dev_registry)
             ```
         """
-        for name, fixture in registry._fixtures.items():
+        for name, variants in registry._fixtures.items():
-            if name in self._fixtures:
+            for fixture in variants:
-                raise ValueError(
+                self._validate_no_context_overlap(name, fixture.contexts)
-                    f"Fixture '{name}' already exists in the current registry"
+                self._fixtures.setdefault(name, []).append(fixture)
-                )
-            self._fixtures[name] = fixture
 
     def get(self, name: str) -> Fixture:
-        """Get a fixture by name."""
+        """Get a fixture by name.
+
+        Raises:
+            KeyError: If no fixture with *name* is registered.
+            ValueError: If the fixture has multiple context variants — use
+                :meth:`get_variants` in that case.
+        """
         if name not in self._fixtures:
             raise KeyError(f"Fixture '{name}' not found")
-        return self._fixtures[name]
+        variants = self._fixtures[name]
+        if len(variants) > 1:
+            raise ValueError(
+                f"Fixture '{name}' has {len(variants)} context variants. "
+                f"Use get_variants('{name}') to retrieve them."
+            )
+        return variants[0]
+
+    def get_variants(self, name: str, *contexts: str | Enum) -> list[Fixture]:
+        """Return all registered variants for *name*, optionally filtered by context.
+
+        Args:
+            name: Fixture name.
+            *contexts: If given, only return variants whose context set
+                intersects with these values.  Both :class:`Context` enum
+                values and plain strings are accepted.
+
+        Returns:
+            List of matching :class:`Fixture` objects (may be empty when a
+            context filter is applied and nothing matches).
+
+        Raises:
+            KeyError: If no fixture with *name* is registered.
+        """
+        if name not in self._fixtures:
+            raise KeyError(f"Fixture '{name}' not found")
+        variants = self._fixtures[name]
+        if not contexts:
+            return list(variants)
+        context_values = set(_normalize_contexts(contexts))
+        return [v for v in variants if set(v.contexts) & context_values]
 
     def get_all(self) -> list[Fixture]:
-        """Get all registered fixtures."""
+        """Get all registered fixtures (all variants of all names)."""
-        return list(self._fixtures.values())
+        return [f for variants in self._fixtures.values() for f in variants]
 
-    def get_by_context(self, *contexts: str | Context) -> list[Fixture]:
+    def get_by_context(self, *contexts: str | Enum) -> list[Fixture]:
         """Get fixtures for specific contexts."""
-        context_values = {c.value if isinstance(c, Context) else c for c in contexts}
+        context_values = set(_normalize_contexts(contexts))
-        return [f for f in self._fixtures.values() if set(f.contexts) & context_values]
+        return [
+            f
+            for variants in self._fixtures.values()
+            for f in variants
+            if set(f.contexts) & context_values
+        ]
 
     def resolve_dependencies(self, *names: str) -> list[str]:
         """Resolve fixture dependencies in topological order.
 
+        When a fixture name has multiple context variants, the union of all
+        variants' ``depends_on`` lists is used.
+
         Args:
             *names: Fixture names to resolve
 
@@ -185,9 +264,20 @@ class FixtureRegistry:
                 raise ValueError(f"Circular dependency detected: {name}")
 
             visiting.add(name)
-            fixture = self.get(name)
+            variants = self._fixtures.get(name)
+            if variants is None:
+                raise KeyError(f"Fixture '{name}' not found")
 
-            for dep in fixture.depends_on:
+            # Union of depends_on across all variants, preserving first-seen order.
+            seen_deps: set[str] = set()
+            all_deps: list[str] = []
+            for variant in variants:
+                for dep in variant.depends_on:
+                    if dep not in seen_deps:
+                        all_deps.append(dep)
+                        seen_deps.add(dep)
+
+            for dep in all_deps:
                 visit(dep)
 
             visiting.remove(name)
@@ -199,7 +289,7 @@ class FixtureRegistry:
 
         return resolved
 
-    def resolve_context_dependencies(self, *contexts: str | Context) -> list[str]:
+    def resolve_context_dependencies(self, *contexts: str | Enum) -> list[str]:
         """Resolve all fixtures for contexts with dependencies.
 
         Args:
@@ -209,7 +299,9 @@ class FixtureRegistry:
             List of fixture names in load order
         """
         context_fixtures = self.get_by_context(*contexts)
-        names = [f.name for f in context_fixtures]
+        # Deduplicate names while preserving first-seen order (a name can
+        # appear multiple times if it has variants in different contexts).
+        names = list(dict.fromkeys(f.name for f in context_fixtures))
 
         all_deps: set[str] = set()
         for name in names:

src/fastapi_toolsets/fixtures/utils.py

@@ -1,8 +1,11 @@
 """Fixture loading utilities for database seeding."""
 
 from collections.abc import Callable, Sequence
+from enum import Enum
 from typing import Any
 
+from sqlalchemy import inspect as sa_inspect
+from sqlalchemy.dialects.postgresql import insert as pg_insert
 from sqlalchemy.ext.asyncio import AsyncSession
 from sqlalchemy.orm import DeclarativeBase
 
@@ -10,23 +13,163 @@ from ..db import get_transaction
 from ..logger import get_logger
 from ..types import ModelType
 from .enum import LoadStrategy
-from .registry import Context, FixtureRegistry
+from .registry import FixtureRegistry, _normalize_contexts
 
 logger = get_logger()
 
 
+def _instance_to_dict(instance: DeclarativeBase) -> dict[str, Any]:
+    """Extract column values from a model instance, skipping unset server-default columns."""
+    state = sa_inspect(instance)
+    state_dict = state.dict
+    result: dict[str, Any] = {}
+    for prop in state.mapper.column_attrs:
+        if prop.key not in state_dict:
+            continue
+        val = state_dict[prop.key]
+        if val is None:
+            col = prop.columns[0]
+
+            if col.server_default is not None or (
+                col.default is not None and col.default.is_callable
+            ):
+                continue
+        result[prop.key] = val
+    return result
+
+
+def _normalize_rows(dicts: list[dict[str, Any]]) -> list[dict[str, Any]]:
+    """Ensure all row dicts share the same key set."""
+    all_keys: set[str] = set().union(*dicts)
+    return [{k: d.get(k) for k in all_keys} for d in dicts]
+
+
+def _group_by_type(
+    instances: list[DeclarativeBase],
+) -> list[tuple[type[DeclarativeBase], list[DeclarativeBase]]]:
+    """Group instances by their concrete model class, preserving insertion order."""
+    groups: dict[type[DeclarativeBase], list[DeclarativeBase]] = {}
+    for instance in instances:
+        groups.setdefault(type(instance), []).append(instance)
+    return list(groups.items())
+
+
+async def _batch_insert(
+    session: AsyncSession,
+    model_cls: type[DeclarativeBase],
+    instances: list[DeclarativeBase],
+) -> None:
+    """INSERT all instances — raises on conflict (no duplicate handling)."""
+    dicts = _normalize_rows([_instance_to_dict(i) for i in instances])
+    await session.execute(pg_insert(model_cls).values(dicts))
+
+
+async def _batch_merge(
+    session: AsyncSession,
+    model_cls: type[DeclarativeBase],
+    instances: list[DeclarativeBase],
+) -> None:
+    """UPSERT: insert new rows, update existing ones with the provided values."""
+    mapper = model_cls.__mapper__
+    pk_names = [col.name for col in mapper.primary_key]
+    pk_names_set = set(pk_names)
+    non_pk_cols = [
+        prop.key
+        for prop in mapper.column_attrs
+        if not any(col.name in pk_names_set for col in prop.columns)
+    ]
+
+    dicts = _normalize_rows([_instance_to_dict(i) for i in instances])
+    stmt = pg_insert(model_cls).values(dicts)
+
+    inserted_keys = set(dicts[0]) if dicts else set()
+    update_cols = [col for col in non_pk_cols if col in inserted_keys]
+
+    if update_cols:
+        stmt = stmt.on_conflict_do_update(
+            index_elements=pk_names,
+            set_={col: stmt.excluded[col] for col in update_cols},
+        )
+    else:
+        stmt = stmt.on_conflict_do_nothing(index_elements=pk_names)
+
+    await session.execute(stmt)
+
+
+async def _batch_skip_existing(
+    session: AsyncSession,
+    model_cls: type[DeclarativeBase],
+    instances: list[DeclarativeBase],
+) -> list[DeclarativeBase]:
+    """INSERT only rows that do not already exist; return the inserted ones."""
+    mapper = model_cls.__mapper__
+    pk_names = [col.name for col in mapper.primary_key]
+
+    no_pk: list[DeclarativeBase] = []
+    with_pk_pairs: list[tuple[DeclarativeBase, Any]] = []
+    for inst in instances:
+        pk = _get_primary_key(inst)
+        if pk is None:
+            no_pk.append(inst)
+        else:
+            with_pk_pairs.append((inst, pk))
+
+    loaded: list[DeclarativeBase] = list(no_pk)
+    if no_pk:
+        await session.execute(
+            pg_insert(model_cls).values(
+                _normalize_rows([_instance_to_dict(i) for i in no_pk])
+            )
+        )
+
+    if with_pk_pairs:
+        with_pk = [i for i, _ in with_pk_pairs]
+        stmt = (
+            pg_insert(model_cls)
+            .values(_normalize_rows([_instance_to_dict(i) for i in with_pk]))
+            .on_conflict_do_nothing(index_elements=pk_names)
+        )
+        result = await session.execute(stmt.returning(*mapper.primary_key))
+        inserted_pks = {row[0] if len(pk_names) == 1 else tuple(row) for row in result}
+        loaded.extend(inst for inst, pk in with_pk_pairs if pk in inserted_pks)
+
+    return loaded
+
+
 async def _load_ordered(
     session: AsyncSession,
     registry: FixtureRegistry,
     ordered_names: list[str],
     strategy: LoadStrategy,
+    contexts: tuple[str, ...] | None = None,
 ) -> dict[str, list[DeclarativeBase]]:
-    """Load fixtures in order."""
+    """Load fixtures in order using batch Core INSERT statements.
+
+    When *contexts* is provided only variants whose context set intersects with
+    *contexts* are called for each name; their instances are concatenated.
+    When *contexts* is ``None`` all variants of each name are loaded.
+    """
     results: dict[str, list[DeclarativeBase]] = {}
 
     for name in ordered_names:
-        fixture = registry.get(name)
+        variants = (
-        instances = list(fixture.func())
+            registry.get_variants(name, *contexts)
+            if contexts is not None
+            else registry.get_variants(name)
+        )
+
+        # Cross-context dependency fallback: if we're loading by context but
+        # no variant matches (e.g. a "base"-only fixture required by a
+        # "testing" fixture), load all available variants so the dependency
+        # is satisfied.
+        if contexts is not None and not variants:
+            variants = registry.get_variants(name)
+
+        if not variants:
+            results[name] = []
+            continue
+
+        instances = [inst for v in variants for inst in v.func()]
 
         if not instances:
             results[name] = []
@@ -36,25 +179,17 @@ async def _load_ordered(
         loaded: list[DeclarativeBase] = []
 
         async with get_transaction(session):
-            for instance in instances:
+            for model_cls, group in _group_by_type(instances):
-                if strategy == LoadStrategy.INSERT:
+                match strategy:
-                    session.add(instance)
+                    case LoadStrategy.INSERT:
-                    loaded.append(instance)
+                        await _batch_insert(session, model_cls, group)
-
+                        loaded.extend(group)
-                elif strategy == LoadStrategy.MERGE:
+                    case LoadStrategy.MERGE:
-                    merged = await session.merge(instance)
+                        await _batch_merge(session, model_cls, group)
-                    loaded.append(merged)
+                        loaded.extend(group)
-
+                    case LoadStrategy.SKIP_EXISTING:
-                else:  # LoadStrategy.SKIP_EXISTING
+                        inserted = await _batch_skip_existing(session, model_cls, group)
-                    pk = _get_primary_key(instance)
+                        loaded.extend(inserted)
-                    if pk is not None:
-                        existing = await session.get(type(instance), pk)
-                        if existing is None:
-                            session.add(instance)
-                            loaded.append(instance)
-                    else:
-                        session.add(instance)
-                        loaded.append(instance)
 
         results[name] = loaded
         logger.info(f"Loaded fixture '{name}': {len(loaded)} {model_name}(s)")
@@ -109,6 +244,8 @@ async def load_fixtures(
 ) -> dict[str, list[DeclarativeBase]]:
     """Load specific fixtures by name with dependencies.
 
+    All context variants of each requested fixture are loaded and merged.
+
     Args:
         session: Database session
         registry: Fixture registry
@@ -125,19 +262,27 @@ async def load_fixtures(
 async def load_fixtures_by_context(
     session: AsyncSession,
     registry: FixtureRegistry,
-    *contexts: str | Context,
+    *contexts: str | Enum,
     strategy: LoadStrategy = LoadStrategy.MERGE,
 ) -> dict[str, list[DeclarativeBase]]:
     """Load all fixtures for specific contexts.
 
+    For each fixture name, only the variants whose context set intersects with
+    *contexts* are loaded.  When a name has variants in multiple of the
+    requested contexts, their instances are merged before being inserted.
+
     Args:
         session: Database session
         registry: Fixture registry
-        *contexts: Contexts to load (e.g., Context.BASE, Context.TESTING)
+        *contexts: Contexts to load (e.g., ``Context.BASE``, ``Context.TESTING``,
+            or plain strings for custom contexts)
         strategy: How to handle existing records
 
     Returns:
         Dict mapping fixture names to loaded instances
     """
+    context_strings = tuple(_normalize_contexts(contexts))
     ordered = registry.resolve_context_dependencies(*contexts)
-    return await _load_ordered(session, registry, ordered, strategy)
+    return await _load_ordered(
+        session, registry, ordered, strategy, contexts=context_strings
+    )

src/fastapi_toolsets/models/watched.py

@@ -27,6 +27,7 @@ _SESSION_CREATES = "_ft_creates"
 _SESSION_DELETES = "_ft_deletes"
 _SESSION_UPDATES = "_ft_updates"
 _SESSION_SAVEPOINT_DEPTH = "_ft_sp_depth"
+_DEFERRED_STRATEGY_KEY = (("deferred", True), ("instrument", True))
 
 
 class ModelEvent(str, Enum):
@@ -60,11 +61,22 @@ def _snapshot_column_attrs(obj: Any) -> dict[str, Any]:
     """Read currently-loaded column values into a plain dict."""
     state = sa_inspect(obj)  # InstanceState
     state_dict = state.dict
-    return {
+    snapshot: dict[str, Any] = {}
-        prop.key: state_dict[prop.key]
+    for prop in state.mapper.column_attrs:
-        for prop in state.mapper.column_attrs
+        if prop.key in state_dict:
-        if prop.key in state_dict
+            snapshot[prop.key] = state_dict[prop.key]
-    }
+        elif (
+            not state.expired
+            and prop.strategy_key != _DEFERRED_STRATEGY_KEY
+            and all(
+                col.nullable
+                and col.server_default is None
+                and col.server_onupdate is None
+                for col in prop.columns
+            )
+        ):
+            snapshot[prop.key] = None
+    return snapshot
 
 
 def _get_watched_fields(cls: type) -> list[str] | None:

src/fastapi_toolsets/pytest/utils.py

@@ -7,6 +7,7 @@ from contextlib import asynccontextmanager
 from typing import Any
 
 from httpx import ASGITransport, AsyncClient
+from sqlalchemy import text
 from sqlalchemy.engine import make_url
 from sqlalchemy.ext.asyncio import (
     AsyncSession,
@@ -15,13 +16,8 @@ from sqlalchemy.ext.asyncio import (
 )
 from sqlalchemy.orm import DeclarativeBase
 
-from sqlalchemy import text
+from ..db import cleanup_tables as _cleanup_tables
-
+from ..db import create_database
-from ..db import (
-    cleanup_tables as _cleanup_tables,
-    create_database,
-    create_db_context,
-)
 
 
 async def cleanup_tables(
@@ -269,15 +265,12 @@ async def create_db_session(
         async with engine.begin() as conn:
             await conn.run_sync(base.metadata.create_all)
 
-        # Create session using existing db context utility
         session_maker = async_sessionmaker(engine, expire_on_commit=expire_on_commit)
-        get_session = create_db_context(session_maker)
+        async with session_maker() as session:
-
-        async with get_session() as session:
             yield session
 
             if cleanup:
-                await cleanup_tables(session, base)
+                await _cleanup_tables(session=session, base=base)
 
         if drop_tables:
             async with engine.begin() as conn:

tests/conftest.py

@@ -57,6 +57,7 @@ class User(Base):
     username: Mapped[str] = mapped_column(String(50), unique=True)
     email: Mapped[str] = mapped_column(String(100), unique=True)
     is_active: Mapped[bool] = mapped_column(default=True)
+    notes: Mapped[str | None]
     role_id: Mapped[uuid.UUID | None] = mapped_column(
         ForeignKey("roles.id"), nullable=True
     )

tests/test_crud_search.py

@@ -646,7 +646,7 @@ class TestFacetsRelationship:
         result = await UserRelFacetCrud.offset_paginate(db_session, schema=UserRead)
 
         assert result.filter_attributes is not None
-        assert set(result.filter_attributes["name"]) == {"admin", "editor"}
+        assert set(result.filter_attributes["role__name"]) == {"admin", "editor"}
 
     @pytest.mark.anyio
     async def test_relationship_facet_none_excluded(self, db_session: AsyncSession):
@@ -661,7 +661,7 @@ class TestFacetsRelationship:
         result = await UserRelFacetCrud.offset_paginate(db_session, schema=UserRead)
 
         assert result.filter_attributes is not None
-        assert result.filter_attributes["name"] == []
+        assert result.filter_attributes["role__name"] == []
 
     @pytest.mark.anyio
     async def test_relationship_facet_deduplicates_join_with_search(
@@ -689,7 +689,7 @@ class TestFacetsRelationship:
         )
 
         assert result.filter_attributes is not None
-        assert result.filter_attributes["name"] == ["admin"]
+        assert result.filter_attributes["role__name"] == ["admin"]
 
 
 class TestFilterBy:
@@ -755,7 +755,7 @@ class TestFilterBy:
         )
 
         result = await UserRelFacetCrud.offset_paginate(
-            db_session, filter_by={"name": "admin"}, schema=UserRead
+            db_session, filter_by={"role__name": "admin"}, schema=UserRead
         )
 
         assert isinstance(result.pagination, OffsetPagination)
@@ -824,7 +824,7 @@ class TestFilterBy:
 
         result = await UserRoleFacetCrud.offset_paginate(
             db_session,
-            filter_by={"name": "admin", "id": str(admin.id)},
+            filter_by={"role__name": "admin", "role__id": str(admin.id)},
             schema=UserRead,
         )
 
@@ -916,15 +916,15 @@ class TestFilterParamsSchema:
         param_names = set(inspect.signature(dep).parameters)
         assert param_names == {"username", "email"}
 
-    def test_relationship_facet_uses_column_key(self):
+    def test_relationship_facet_uses_full_chain_key(self):
-        """Relationship tuple uses the terminal column's key."""
+        """Relationship tuple uses the full chain joined by __ as the key."""
         import inspect
 
         UserRoleCrud = CrudFactory(User, facet_fields=[(User.role, Role.name)])
         dep = UserRoleCrud.filter_params()
 
         param_names = set(inspect.signature(dep).parameters)
-        assert param_names == {"name"}
+        assert param_names == {"role__name"}
 
     def test_raises_when_no_facet_fields(self):
         """ValueError raised when no facet_fields are configured or provided."""
@@ -978,6 +978,22 @@ class TestFilterParamsSchema:
         keys = facet_keys([(rel_a, col_a), (rel_b, col_b)])
         assert keys == ["project__name", "os__name"]
 
+    def test_deep_chain_joins_all_segments(self):
+        """Three-element tuple produces all relation segments joined by __."""
+        from unittest.mock import MagicMock
+
+        from fastapi_toolsets.crud.search import facet_keys
+
+        rel_a = MagicMock()
+        rel_a.key = "role"
+        rel_b = MagicMock()
+        rel_b.key = "permission"
+        col = MagicMock()
+        col.key = "name"
+
+        keys = facet_keys([(rel_a, rel_b, col)])
+        assert keys == ["role__permission__name"]
+
     def test_unique_column_keys_kept_plain(self):
         """Fields with unique column keys are not prefixed."""
         from fastapi_toolsets.crud.search import facet_keys

tests/test_example_pagination_search.py

@@ -97,7 +97,7 @@ class TestAppSessionDep:
         gen = get_db()
         session = await gen.__anext__()
         assert isinstance(session, AsyncSession)
-        await session.close()
+        await gen.aclose()
 
 
 class TestOffsetPagination:
@@ -182,8 +182,7 @@ class TestOffsetPagination:
         body = resp.json()
         fa = body["filter_attributes"]
         assert set(fa["status"]) == {"draft", "published"}
-        # "name" is unique across all facet fields — no prefix needed
+        assert set(fa["category__name"]) == {"backend", "python"}
-        assert set(fa["name"]) == {"backend", "python"}
 
     @pytest.mark.anyio
     async def test_filter_attributes_scoped_to_filter(

tests/test_fixtures.py

@@ -1,6 +1,7 @@
 """Tests for fastapi_toolsets.fixtures module."""
 
 import uuid
+from enum import Enum
 
 import pytest
 from sqlalchemy.ext.asyncio import AsyncSession
@@ -13,10 +14,22 @@ from fastapi_toolsets.fixtures import (
     load_fixtures,
     load_fixtures_by_context,
 )
+from fastapi_toolsets.fixtures.utils import _get_primary_key, _instance_to_dict
 
-from fastapi_toolsets.fixtures.utils import _get_primary_key
+from .conftest import IntRole, Permission, Role, RoleCreate, RoleCrud, User, UserCrud
 
-from .conftest import IntRole, Permission, Role, RoleCrud, User, UserCrud
+
+class AppContext(str, Enum):
+    """Example user-defined str+Enum context."""
+
+    STAGING = "staging"
+    DEMO = "demo"
+
+
+class PlainEnumContext(Enum):
+    """Example user-defined plain Enum context (no str mixin)."""
+
+    STAGING = "staging"
 
 
 class TestContext:
@@ -39,6 +52,86 @@ class TestContext:
         assert Context.TESTING.value == "testing"
 
 
+class TestCustomEnumContext:
+    """Custom Enum types are accepted wherever Context/str are expected."""
+
+    def test_cannot_subclass_context_with_members(self):
+        """Python prohibits extending an Enum that already has members."""
+        with pytest.raises(TypeError):
+
+            class MyContext(Context):  # noqa: F841  # ty: ignore[subclass-of-final-class]
+                STAGING = "staging"
+
+    def test_custom_enum_values_interchangeable_with_context(self):
+        """A custom enum with the same .value as a built-in Context member is
+        treated as the same context — fixtures registered under one are found
+        by the other."""
+
+        class AppContextFull(str, Enum):
+            BASE = "base"
+            STAGING = "staging"
+
+        registry = FixtureRegistry()
+
+        @registry.register(contexts=[Context.BASE])
+        def roles():
+            return []
+
+        # AppContextFull.BASE has value "base" — same as Context.BASE
+        fixtures = registry.get_by_context(AppContextFull.BASE)
+        assert len(fixtures) == 1
+
+    def test_custom_enum_registry_default_contexts(self):
+        """FixtureRegistry(contexts=[...]) accepts a custom Enum."""
+        registry = FixtureRegistry(contexts=[AppContext.STAGING])
+
+        @registry.register
+        def data():
+            return []
+
+        fixture = registry.get("data")
+        assert fixture.contexts == ["staging"]
+
+    def test_custom_enum_resolve_context_dependencies(self):
+        """resolve_context_dependencies accepts a custom Enum context."""
+        registry = FixtureRegistry()
+
+        @registry.register(contexts=[AppContext.STAGING])
+        def staging_roles():
+            return []
+
+        order = registry.resolve_context_dependencies(AppContext.STAGING)
+        assert "staging_roles" in order
+
+    @pytest.mark.anyio
+    async def test_custom_enum_e2e(self, db_session: AsyncSession):
+        """End-to-end: register with custom Enum, load with the same Enum."""
+        registry = FixtureRegistry()
+
+        @registry.register(contexts=[AppContext.STAGING])
+        def staging_roles():
+            return [Role(id=uuid.uuid4(), name="staging-admin")]
+
+        result = await load_fixtures_by_context(
+            db_session, registry, AppContext.STAGING
+        )
+        assert len(result["staging_roles"]) == 1
+
+    @pytest.mark.anyio
+    async def test_plain_enum_e2e(self, db_session: AsyncSession):
+        """End-to-end: register with plain Enum, load with the same Enum."""
+        registry = FixtureRegistry()
+
+        @registry.register(contexts=[PlainEnumContext.STAGING])
+        def staging_roles():
+            return [Role(id=uuid.uuid4(), name="plain-staging-admin")]
+
+        result = await load_fixtures_by_context(
+            db_session, registry, PlainEnumContext.STAGING
+        )
+        assert len(result["staging_roles"]) == 1
+
+
 class TestLoadStrategy:
     """Tests for LoadStrategy enum."""
 
@@ -407,6 +500,37 @@ class TestDependencyResolution:
         with pytest.raises(ValueError, match="Circular dependency"):
             registry.resolve_dependencies("a")
 
+    def test_resolve_raises_for_unknown_dependency(self):
+        """KeyError when depends_on references an unregistered fixture."""
+        registry = FixtureRegistry()
+
+        @registry.register(depends_on=["ghost"])
+        def users():
+            return []
+
+        with pytest.raises(KeyError, match="ghost"):
+            registry.resolve_dependencies("users")
+
+    def test_resolve_deduplicates_shared_depends_on_across_variants(self):
+        """A dep shared by two same-name variants appears only once in the order."""
+        registry = FixtureRegistry()
+
+        @registry.register(contexts=[Context.BASE])
+        def roles():
+            return []
+
+        @registry.register(depends_on=["roles"], contexts=[Context.BASE])
+        def items():
+            return []
+
+        @registry.register(depends_on=["roles"], contexts=[Context.TESTING])
+        def items():  # noqa: F811
+            return []
+
+        order = registry.resolve_dependencies("items")
+        assert order.count("roles") == 1
+        assert order.index("roles") < order.index("items")
+
     def test_resolve_context_dependencies(self):
         """Resolve all fixtures for a context with dependencies."""
         registry = FixtureRegistry()
@@ -496,6 +620,52 @@ class TestLoadFixtures:
         count = await RoleCrud.count(db_session)
         assert count == 1
 
+    @pytest.mark.anyio
+    async def test_merge_does_not_overwrite_omitted_nullable_columns(
+        self, db_session: AsyncSession
+    ):
+        """MERGE must not clear nullable columns that the fixture didn't set.
+
+        When a fixture omits a nullable column (e.g. role_id or notes), a re-merge
+        must leave the existing DB value untouched — not overwrite it with NULL.
+        """
+        registry = FixtureRegistry()
+        admin = await RoleCrud.create(db_session, RoleCreate(name="admin"))
+        uid = uuid.uuid4()
+
+        # First load: user has role_id and notes set
+        @registry.register
+        def users():
+            return [
+                User(
+                    id=uid,
+                    username="alice",
+                    email="a@test.com",
+                    role_id=admin.id,
+                    notes="original",
+                )
+            ]
+
+        await load_fixtures(db_session, registry, "users", strategy=LoadStrategy.MERGE)
+
+        # Second load: fixture omits role_id and notes
+        registry2 = FixtureRegistry()
+
+        @registry2.register
+        def users():  # noqa: F811
+            return [User(id=uid, username="alice-updated", email="a@test.com")]
+
+        await load_fixtures(db_session, registry2, "users", strategy=LoadStrategy.MERGE)
+
+        from sqlalchemy import select
+
+        row = (
+            await db_session.execute(select(User).where(User.id == uid))
+        ).scalar_one()
+        assert row.username == "alice-updated"  # updated column changed
+        assert row.role_id == admin.id  # omitted → preserved
+        assert row.notes == "original"  # omitted → preserved
+
     @pytest.mark.anyio
     async def test_load_with_skip_existing_strategy(self, db_session: AsyncSession):
         """Load fixtures with SKIP_EXISTING strategy."""
@@ -795,3 +965,145 @@ class TestGetPrimaryKey:
         instance = Permission(subject="post")  # action is None
         pk = _get_primary_key(instance)
         assert pk is None
+
+
+class TestRegistryGetVariants:
+    """Tests for FixtureRegistry.get and get_variants edge cases."""
+
+    def test_get_raises_value_error_for_multi_variant(self):
+        """get() raises ValueError when the fixture has multiple context variants."""
+        registry = FixtureRegistry()
+
+        @registry.register(contexts=[Context.BASE])
+        def items():
+            return []
+
+        @registry.register(contexts=[Context.TESTING])
+        def items():  # noqa: F811
+            return []
+
+        with pytest.raises(ValueError, match="get_variants"):
+            registry.get("items")
+
+    def test_get_variants_raises_key_error_for_unknown(self):
+        """get_variants() raises KeyError for an unregistered name."""
+        registry = FixtureRegistry()
+        with pytest.raises(KeyError, match="not found"):
+            registry.get_variants("no_such_fixture")
+
+
+class TestInstanceToDict:
+    """Unit tests for the _instance_to_dict helper."""
+
+    def test_explicit_values_included(self):
+        """All explicitly set column values appear in the result."""
+        role_id = uuid.uuid4()
+        instance = Role(id=role_id, name="admin")
+        d = _instance_to_dict(instance)
+        assert d["id"] == role_id
+        assert d["name"] == "admin"
+
+    def test_callable_default_none_excluded(self):
+        """A column whose value is None but has a callable Python-side default
+        (e.g. ``default=uuid.uuid4``) is excluded so the DB generates it."""
+        instance = Role(id=None, name="admin")
+        d = _instance_to_dict(instance)
+        assert "id" not in d
+        assert d["name"] == "admin"
+
+    def test_nullable_none_included(self):
+        """None on a nullable column with no default is kept (explicit NULL)."""
+        instance = User(id=uuid.uuid4(), username="u", email="e@e.com", role_id=None)
+        d = _instance_to_dict(instance)
+        assert "role_id" in d
+        assert d["role_id"] is None
+
+    def test_nullable_str_no_default_omitted_not_in_dict(self):
+        """Mapped[str | None] with no default, not provided in constructor, is absent from dict."""
+        instance = User(id=uuid.uuid4(), username="u", email="e@e.com")
+        d = _instance_to_dict(instance)
+        assert "notes" not in d
+
+    def test_nullable_str_no_default_explicit_none_included(self):
+        """Mapped[str | None] with no default, explicitly set to None, is included as NULL."""
+        instance = User(id=uuid.uuid4(), username="u", email="e@e.com", notes=None)
+        d = _instance_to_dict(instance)
+        assert "notes" in d
+        assert d["notes"] is None
+
+    def test_nullable_str_no_default_with_value_included(self):
+        """Mapped[str | None] with no default and a value set is included normally."""
+        instance = User(id=uuid.uuid4(), username="u", email="e@e.com", notes="hello")
+        d = _instance_to_dict(instance)
+        assert d["notes"] == "hello"
+
+    @pytest.mark.anyio
+    async def test_nullable_str_no_default_insert_roundtrip(
+        self, db_session: AsyncSession
+    ):
+        """Fixture loading works for models with Mapped[str | None] (no default).
+
+        Both the omitted-value (→ NULL) and explicit-None paths must insert without error.
+        """
+        registry = FixtureRegistry()
+
+        uid_a = uuid.uuid4()
+        uid_b = uuid.uuid4()
+        uid_c = uuid.uuid4()
+
+        @registry.register
+        def users():
+            return [
+                User(
+                    id=uid_a, username="no_notes", email="a@test.com"
+                ),  # notes omitted
+                User(
+                    id=uid_b, username="null_notes", email="b@test.com", notes=None
+                ),  # explicit None
+                User(
+                    id=uid_c, username="has_notes", email="c@test.com", notes="hi"
+                ),  # value set
+            ]
+
+        result = await load_fixtures(db_session, registry, "users")
+
+        from sqlalchemy import select
+
+        rows = (
+            (await db_session.execute(select(User).order_by(User.username)))
+            .scalars()
+            .all()
+        )
+        by_username = {r.username: r for r in rows}
+
+        assert by_username["no_notes"].notes is None
+        assert by_username["null_notes"].notes is None
+        assert by_username["has_notes"].notes == "hi"
+        assert len(result["users"]) == 3
+
+
+class TestBatchMergeNonPkColumns:
+    """Batch MERGE on a model with no non-PK columns (PK-only table)."""
+
+    @pytest.mark.anyio
+    async def test_merge_pk_only_model(self, db_session: AsyncSession):
+        """MERGE strategy on a PK-only model uses on_conflict_do_nothing."""
+        registry = FixtureRegistry()
+
+        @registry.register
+        def permissions():
+            return [
+                Permission(subject="post", action="read"),
+                Permission(subject="post", action="write"),
+            ]
+
+        result = await load_fixtures(
+            db_session, registry, "permissions", strategy=LoadStrategy.MERGE
+        )
+        assert len(result["permissions"]) == 2
+
+        # Run again — conflicts are silently ignored.
+        result2 = await load_fixtures(
+            db_session, registry, "permissions", strategy=LoadStrategy.MERGE
+        )
+        assert len(result2["permissions"]) == 2

tests/test_models.py

@@ -32,6 +32,7 @@ from fastapi_toolsets.models.watched import (
     _after_flush,
     _after_flush_postexec,
     _after_rollback,
+    _snapshot_column_attrs,
     _task_error_handler,
     _upsert_changes,
 )
@@ -213,20 +214,36 @@ class AttrAccessModel(MixinBase, UUIDMixin, WatchedFieldsMixin):
     __tablename__ = "mixin_attr_access_models"
 
     name: Mapped[str] = mapped_column(String(50))
+    callback_url: Mapped[str | None] = mapped_column(String(200), nullable=True)
 
     async def on_create(self) -> None:
         _attr_access_events.append(
-            {"event": "create", "id": self.id, "name": self.name}
+            {
+                "event": "create",
+                "id": self.id,
+                "name": self.name,
+                "callback_url": self.callback_url,
+            }
         )
 
     async def on_delete(self) -> None:
         _attr_access_events.append(
-            {"event": "delete", "id": self.id, "name": self.name}
+            {
+                "event": "delete",
+                "id": self.id,
+                "name": self.name,
+                "callback_url": self.callback_url,
+            }
         )
 
     async def on_update(self, changes: dict) -> None:
         _attr_access_events.append(
-            {"event": "update", "id": self.id, "name": self.name}
+            {
+                "event": "update",
+                "id": self.id,
+                "name": self.name,
+                "callback_url": self.callback_url,
+            }
         )
 
 
@@ -1279,3 +1296,67 @@ class TestAttributeAccessInCallbacks:
         assert len(events) == 1
         assert isinstance(events[0]["id"], uuid.UUID)
         assert events[0]["name"] == "updated"
+
+    @pytest.mark.anyio
+    async def test_nullable_column_none_accessible_in_on_create(
+        self, mixin_session_expire
+    ):
+        """Nullable column left as None is accessible in on_create without greenlet error."""
+        obj = AttrAccessModel(name="no-url")  # callback_url not set → None
+        mixin_session_expire.add(obj)
+        await mixin_session_expire.commit()
+        await asyncio.sleep(0)
+
+        events = [e for e in _attr_access_events if e["event"] == "create"]
+        assert len(events) == 1
+        assert events[0]["callback_url"] is None
+
+    @pytest.mark.anyio
+    async def test_nullable_column_with_value_accessible_in_on_create(
+        self, mixin_session_expire
+    ):
+        """Nullable column set to a value is accessible in on_create without greenlet error."""
+        obj = AttrAccessModel(name="with-url", callback_url="https://example.com/hook")
+        mixin_session_expire.add(obj)
+        await mixin_session_expire.commit()
+        await asyncio.sleep(0)
+
+        events = [e for e in _attr_access_events if e["event"] == "create"]
+        assert len(events) == 1
+        assert events[0]["callback_url"] == "https://example.com/hook"
+
+    @pytest.mark.anyio
+    async def test_nullable_column_accessible_after_update_to_none(
+        self, mixin_session_expire
+    ):
+        """Nullable column updated to None is accessible in on_update without greenlet error."""
+        obj = AttrAccessModel(name="x", callback_url="https://example.com/hook")
+        mixin_session_expire.add(obj)
+        await mixin_session_expire.commit()
+        await asyncio.sleep(0)
+        _attr_access_events.clear()
+
+        obj.callback_url = None
+        await mixin_session_expire.commit()
+        await asyncio.sleep(0)
+
+        events = [e for e in _attr_access_events if e["event"] == "update"]
+        assert len(events) == 1
+        assert events[0]["callback_url"] is None
+
+    @pytest.mark.anyio
+    async def test_expired_nullable_column_not_inferred_as_none(
+        self, mixin_session_expire
+    ):
+        """A nullable column with a real value that is expired (by a prior
+        expire_on_commit) must not be inferred as None in the snapshot — its
+        actual value is unknown without a DB refresh."""
+        obj = AttrAccessModel(name="original", callback_url="https://example.com/hook")
+        mixin_session_expire.add(obj)
+        await mixin_session_expire.commit()
+        # expire_on_commit fired → obj.state.expired=True, callback_url not in state.dict
+
+        snapshot = _snapshot_column_attrs(obj)
+
+        # callback_url has a real DB value but is expired — must not be snapshotted as None.
+        assert "callback_url" not in snapshot

tests/test_pytest.py

@@ -7,9 +7,10 @@ from fastapi import Depends, FastAPI
 from httpx import AsyncClient
 from sqlalchemy import select, text
 from sqlalchemy.engine import make_url
-from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine
+from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
 from sqlalchemy.orm import selectinload
 
+from fastapi_toolsets.db import get_transaction
 from fastapi_toolsets.fixtures import Context, FixtureRegistry
 from fastapi_toolsets.pytest import (
     create_async_client,
@@ -336,6 +337,55 @@ class TestCreateDbSession:
             result = await session.execute(select(Role))
             assert result.all() == []
 
+    @pytest.mark.anyio
+    async def test_get_transaction_commits_visible_to_separate_session(self):
+        """Data written via get_transaction() is committed and visible to other sessions."""
+        role_id = uuid.uuid4()
+
+        async with create_db_session(DATABASE_URL, Base, drop_tables=False) as session:
+            # Simulate what _create_fixture_function does: insert via get_transaction
+            # with no explicit commit afterward.
+            async with get_transaction(session):
+                role = Role(id=role_id, name="visible_to_other_session")
+                session.add(role)
+
+            # The data must have been committed (begin/commit, not a savepoint),
+            # so a separate engine/session can read it.
+            other_engine = create_async_engine(DATABASE_URL, echo=False)
+            try:
+                other_session_maker = async_sessionmaker(
+                    other_engine, expire_on_commit=False
+                )
+                async with other_session_maker() as other:
+                    result = await other.execute(select(Role).where(Role.id == role_id))
+                    fetched = result.scalar_one_or_none()
+                    assert fetched is not None, (
+                        "Fixture data inserted via get_transaction() must be committed "
+                        "and visible to a separate session. If create_db_session uses "
+                        "create_db_context, auto-begin forces get_transaction() into "
+                        "savepoints instead of real commits."
+                    )
+                    assert fetched.name == "visible_to_other_session"
+            finally:
+                await other_engine.dispose()
+
+        # Cleanup
+        async with create_db_session(DATABASE_URL, Base, drop_tables=True) as _:
+            pass
+
+
+class TestDeprecatedCleanupTables:
+    """Tests for the deprecated cleanup_tables re-export in fastapi_toolsets.pytest."""
+
+    @pytest.mark.anyio
+    async def test_emits_deprecation_warning(self):
+        """cleanup_tables imported from fastapi_toolsets.pytest emits DeprecationWarning."""
+        from fastapi_toolsets.pytest.utils import cleanup_tables
+
+        async with create_db_session(DATABASE_URL, Base, drop_tables=True) as session:
+            with pytest.warns(DeprecationWarning, match="fastapi_toolsets.db"):
+                await cleanup_tables(session, Base)
+
 
 class TestGetXdistWorker:
     """Tests for _get_xdist_worker helper."""