diff --git a/api/tests/conftest.py b/api/tests/conftest.py
index e69de29..e5eeb18 100644
--- a/api/tests/conftest.py
+++ b/api/tests/conftest.py
@@ -0,0 +1,3 @@
+"""Общие фикстуры тестов."""
+
+pytest_plugins = ["tests.pg_helpers"]
diff --git a/api/tests/pg_helpers.py b/api/tests/pg_helpers.py
new file mode 100644
index 0000000..a924716
--- /dev/null
+++ b/api/tests/pg_helpers.py
@@ -0,0 +1,54 @@
+"""Помощники интеграционных тестов с PostgreSQL: временная БД внутри того же сервера, что и `OPENBAO__DATABASE`.
+
+Фикстура `scratch_db_url` создаёт пустую БД `armcore_scratch_<hex>`, отдаёт её SQLAlchemy-URL (драйвер asyncpg) и
+в конце удаляет. Рабочую БД (`armka`) тесты не трогают. Подключается плагином в `conftest.py`.
+"""
+
+import uuid
+from collections.abc import AsyncIterator
+
+import asyncpg
+import pytest_asyncio
+from sqlalchemy.engine import URL, make_url
+
+from src.core.config import settings
+
+
+def base_url() -> URL:
+    """SQLAlchemy-URL рабочей БД из настроек (`.env.test`)."""
+    return make_url(settings.OPENBAO.DATABASE.DATABASE_URL)
+
+
+def _asyncpg_dsn(url: URL) -> str:
+    return url.set(drivername="postgresql").render_as_string(hide_password=False)
+
+
+async def create_scratch_db(name: str) -> URL:
+    """Создать пустую БД `name` на сервере рабочей БД; вернуть SQLAlchemy-URL на неё."""
+    url = base_url()
+    conn = await asyncpg.connect(_asyncpg_dsn(url))
+    try:
+        await conn.execute(f'CREATE DATABASE "{name}"')
+    finally:
+        await conn.close()
+    return url.set(database=name)
+
+
+async def drop_scratch_db(name: str) -> None:
+    """Удалить БД `name` (закрывая оставшиеся подключения)."""
+    conn = await asyncpg.connect(_asyncpg_dsn(base_url()))
+    try:
+        await conn.execute(f'DROP DATABASE IF EXISTS "{name}" WITH (FORCE)')
+    finally:
+        await conn.close()
+
+
+@pytest_asyncio.fixture
+async def scratch_db_url() -> AsyncIterator[str]:
+    """URL пустой временной БД (asyncpg); БД удаляется после теста."""
+    name = f"armcore_scratch_{uuid.uuid4().hex[:12]}"
+    url = await create_scratch_db(name)
+    try:
+        yield url.render_as_string(hide_password=False)
+    finally:
+        await drop_scratch_db(name)
diff --git a/api/tests/test_models_part_01_03.py b/api/tests/test_models_part_01_03.py
new file mode 100644
index 0000000..00e8f75
--- /dev/null
+++ b/api/tests/test_models_part_01_03.py
@@ -0,0 +1,210 @@
+"""ORM частей 01–03 DBML v5.13 (справочники, доступ, учёт): чётность с DBML без БД и create_all на PostgreSQL."""
+
+import datetime
+import uuid
+
+import pytest
+from pydbml.classes import Table as DbmlTable
+from sqlalchemy import Table, inspect, text
+from sqlalchemy.dialects import postgresql
+from sqlalchemy.exc import IntegrityError
+from sqlalchemy.ext.asyncio import create_async_engine
+from sqlalchemy.schema import CreateIndex, CreateTable
+
+from src.models import Base
+from tests.dbml_helpers import load_dbml
+
+PART_01_03_TABLES = {
+    # directories
+    "regional_office",
+    "company_group",
+    "company_group_history",
+    "legal_entity",
+    "legal_entity_history",
+    "legal_entity_alias",
+    "related_group",
+    "related_group_member",
+    # access
+    "app_user",
+    "role",
+    "permission",
+    "role_permission",
+    "user_role",
+    # accounting
+    "chart_of_account",
+    "elimination_rule",
+    "elimination_rule_account",
+}
+PG_IDENTIFIER_LIMIT = 63
+EXPECTED_TABLE_COUNT = 16
+
+
+def orm_tables() -> dict[str, Table]:
+    return {t.name: t for t in Base.metadata.sorted_tables}
+
+
+def dbml_tables() -> dict[str, DbmlTable]:
+    return {t.name: t for t in load_dbml().tables if t.name in PART_01_03_TABLES}
+
+
+def test_part_01_03_tables_registered_in_metadata() -> None:
+    assert set(orm_tables()) == PART_01_03_TABLES
+    assert len(Base.metadata.sorted_tables) == EXPECTED_TABLE_COUNT  # на этом этапе (задачи 7–8 добавят остальные)
+    assert all(t.schema == "dkb" for t in Base.metadata.sorted_tables)
+
+
+def test_every_table_and_index_compiles_for_postgresql() -> None:
+    dialect = postgresql.dialect()
+    for table in Base.metadata.sorted_tables:
+        assert str(CreateTable(table).compile(dialect=dialect)).strip()
+        for index in table.indexes:
+            assert str(CreateIndex(index).compile(dialect=dialect)).strip()
+
+
+def test_foreign_keys_resolve_to_registered_tables() -> None:
+    for table in Base.metadata.sorted_tables:
+        for fk in table.foreign_keys:
+            assert fk.column.table.key in Base.metadata.tables, f"{table.name}.{fk.parent.name}"
+            assert fk.column.table.schema == "dkb"
+
+
+def test_constraint_names_are_explicit_and_fit_postgres_limit() -> None:
+    """Все имена ограничений заданы (конвенцией/явно), без хеш-усечения, и не длиннее 63 символов."""
+    for table in Base.metadata.sorted_tables:
+        names = [c.name for c in table.constraints] + [i.name for i in table.indexes]
+        for name in names:
+            assert name, f"{table.name}: безымянное ограничение"
+            assert len(str(name)) <= PG_IDENTIFIER_LIMIT, f"{table.name}: {name} длиннее {PG_IDENTIFIER_LIMIT}"
+
+
+def test_columns_match_dbml() -> None:
+    """Имена колонок, nullability, PK и FK-цели — как в DBML."""
+    orm, dbml = orm_tables(), dbml_tables()
+    refs = [r for r in load_dbml().refs if r.table1.name in PART_01_03_TABLES]
+    expected_fks = {(r.table1.name, r.col1[0].name, r.table2.name, r.col2[0].name) for r in refs}
+    actual_fks = {
+        (t.name, fk.parent.name, fk.column.table.name, fk.column.name) for t in orm.values() for fk in t.foreign_keys
+    }
+    assert actual_fks == expected_fks
+    for name, dbml_table in dbml.items():
+        orm_table = orm[name]
+        dbml_cols = {c.name: c for c in dbml_table.columns}
+        assert set(orm_table.columns.keys()) == set(dbml_cols), name
+        composite_pk = {c.name for i in dbml_table.indexes if i.pk for c in i.subjects}
+        for col_name, dbml_col in dbml_cols.items():
+            orm_col = orm_table.columns[col_name]
+            is_pk = dbml_col.pk or col_name in composite_pk
+            assert orm_col.primary_key == is_pk, f"{name}.{col_name}: pk"
+            assert orm_col.nullable == (not (dbml_col.not_null or is_pk)), f"{name}.{col_name}: nullable"
+            assert bool(orm_col.unique) == bool(dbml_col.unique), f"{name}.{col_name}: unique"
+            if dbml_col.default is None:
+                assert orm_col.server_default is None, f"{name}.{col_name}: лишний server_default"
+            else:
+                assert orm_col.server_default is not None, f"{name}.{col_name}: нет server_default"
+                assert str(orm_col.server_default.arg).lower() == str(dbml_col.default).lower()
+
+
+def test_column_order_follows_dbml() -> None:
+    """Порядок колонок как в DBML (в частности `id` первой) — миграция 0001 читается рядом с DBML."""
+    orm = orm_tables()
+    for name, dbml_table in dbml_tables().items():
+        assert [c.name for c in orm[name].columns] == [c.name for c in dbml_table.columns], name
+
+
+def test_indexes_match_dbml() -> None:
+    """Состав индексов (кроме PK): колонки, уникальность, partial-условие."""
+    orm = orm_tables()
+    for name, dbml_table in dbml_tables().items():
+        expected = sorted(
+            (tuple(c.name for c in i.subjects), i.unique or "partial UNIQUE" in str(i.note))
+            for i in dbml_table.indexes
+            if not i.pk
+        )
+        actual = sorted((tuple(c.name for c in i.columns), bool(i.unique)) for i in orm[name].indexes)
+        assert actual == expected, name
+    partial = {i.name: str(i.dialect_options["postgresql"]["where"]) for i in orm["related_group_member"].indexes}
+    assert partial == {
+        "uq_related_group_member_group_entity_current": "is_current",
+        "uq_related_group_member_entity_current": "is_current",
+    }
+
+
+@pytest.mark.integration
+async def test_create_all_on_scratch_db(scratch_db_url: str) -> None:
+    """`create_all` на пустой БД: 16 таблиц в схеме dkb, enum-типы, partial unique работают."""
+    engine = create_async_engine(scratch_db_url)
+    try:
+        async with engine.begin() as conn:
+            await conn.execute(text("CREATE SCHEMA IF NOT EXISTS dkb"))
+            await conn.run_sync(Base.metadata.create_all)
+
+        async with engine.connect() as conn:
+            tables = await conn.run_sync(lambda c: set(inspect(c).get_table_names(schema="dkb")))
+            assert tables == PART_01_03_TABLES
+            enums = {
+                row[0]
+                for row in await conn.execute(
+                    text(
+                        "SELECT t.typname FROM pg_type t JOIN pg_namespace n ON n.oid = t.typnamespace "
+                        "WHERE n.nspname = 'dkb' AND t.typtype = 'e'"
+                    )
+                )
+            }
+            assert enums == {
+                "entity_type", "related_group_kind", "account_kind", "account_row_type", "business_segment",
+                "statement_type", "le_history_event", "permission_object", "permission_action",
+            }  # fmt: skip
+            indexdefs = {
+                row[0]: row[1]
+                for row in await conn.execute(
+                    text(
+                        "SELECT indexname, indexdef FROM pg_indexes WHERE schemaname = 'dkb' "
+                        "AND tablename = 'related_group_member'"
+                    )
+                )
+            }
+            for name in ("uq_related_group_member_group_entity_current", "uq_related_group_member_entity_current"):
+                assert "UNIQUE" in indexdefs[name]
+                assert "WHERE is_current" in indexdefs[name]
+            pk = await conn.run_sync(lambda c: inspect(c).get_pk_constraint("role_permission", schema="dkb"))
+            assert pk["name"] == "pk_role_permission"
+            assert pk["constrained_columns"] == ["role_id", "permission_id"]
+
+        await _check_related_group_member_uniqueness(engine)
+    finally:
+        await engine.dispose()
+
+
+async def _check_related_group_member_uniqueness(engine) -> None:  # type: ignore[no-untyped-def]
+    """ЮЛ — только в одной ГСК/ГСЗ среди текущих; закрытая версия не мешает (ТЗ 6.1, ANL-030)."""
+    now = datetime.datetime.now(datetime.UTC)
+    ids = {k: uuid.uuid4() for k in ("ro", "cg", "le", "g1", "g2", "m1", "m2", "m3")}
+    async with engine.begin() as conn:
+        await conn.execute(text("INSERT INTO dkb.regional_office (id, name) VALUES (:ro, 'ГО')"), ids)
+        await conn.execute(
+            text("INSERT INTO dkb.company_group (id, code, name, valid_from) VALUES (:cg, 'G1', 'ГК', :now)"),
+            {**ids, "now": now},
+        )
+        await conn.execute(
+            text("INSERT INTO dkb.legal_entity (id, inn, name, valid_from) VALUES (:le, '1', 'ЮЛ', :now)"),
+            {**ids, "now": now},
+        )
+        for g, code in (("g1", "GSK-1"), ("g2", "GSK-2")):
+            await conn.execute(
+                text(
+                    "INSERT INTO dkb.related_group (id, code, company_group_id, kind, name) "
+                    "VALUES (:g, :code, :cg, 'gsk', 'ГСК')"
+                ),
+                {"g": ids[g], "code": code, "cg": ids["cg"]},
+            )
+    insert = text(
+        "INSERT INTO dkb.related_group_member (id, related_group_id, legal_entity_id, valid_from, is_current) "
+        "VALUES (:id, :g, :le, :now, :cur)"
+    )
+    async with engine.begin() as conn:
+        await conn.execute(insert, {"id": ids["m1"], "g": ids["g1"], "le": ids["le"], "now": now, "cur": True})
+        # закрытая версия в другой группе — допустима
+        await conn.execute(insert, {"id": ids["m2"], "g": ids["g2"], "le": ids["le"], "now": now, "cur": False})
+    with pytest.raises(IntegrityError):
+        async with engine.begin() as conn:  # второе текущее членство того же ЮЛ — нарушение
+            await conn.execute(insert, {"id": ids["m3"], "g": ids["g2"], "le": ids["le"], "now": now, "cur": True})