From b9ffd74db5d32dc5d35cabe42343583833dc5f83 Mon Sep 17 00:00:00 2001
From: Marcin Ciupak <32123526+mciupak@users.noreply.github.com>
Date: Tue, 21 Sep 2021 00:38:42 +0200
Subject: [PATCH] Fix recorder Oracle DB models (#55564)

* Fix recorder models for Oracle DB

* Fix StatisticsRuns

* Update migration for Oracle Identity columns.

* Update migration logic

Migration to schema version 22 done only for engine dialect oracle

* Add missing table check in schema 22 migration
---
 .../components/recorder/migration.py          | 32 ++++++++++++++++++-
 homeassistant/components/recorder/models.py   |  8 ++---
 2 files changed, 35 insertions(+), 5 deletions(-)

diff --git a/homeassistant/components/recorder/migration.py b/homeassistant/components/recorder/migration.py
index c7ccefeca02..3ceac8903a7 100644
--- a/homeassistant/components/recorder/migration.py
+++ b/homeassistant/components/recorder/migration.py
@@ -20,6 +20,7 @@ from .models import (
     Statistics,
     StatisticsMeta,
     StatisticsRuns,
+    StatisticsShortTerm,
 )
 from .statistics import get_start_time
 from .util import session_scope
@@ -484,7 +485,7 @@ def _apply_update(engine, session, new_version, old_version):  # noqa: C901
         session.add(StatisticsRuns(start=get_start_time()))
     elif new_version == 20:
         # This changed the precision of statistics from float to double
-        if engine.dialect.name in ["mysql", "oracle", "postgresql"]:
+        if engine.dialect.name in ["mysql", "postgresql"]:
             _modify_columns(
                 connection,
                 engine,
@@ -513,6 +514,35 @@ def _apply_update(engine, session, new_version, old_version):  # noqa: C901
                             "CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci"
                         )
                     )
+    elif new_version == 22:
+        # Recreate the all statistics tables for Oracle DB with Identity columns
+        #
+        # Order matters! Statistics has a relation with StatisticsMeta,
+        # so statistics need to be deleted before meta (or in pair depending
+        # on the SQL backend); and meta needs to be created before statistics.
+        if engine.dialect.name == "oracle":
+            if (
+                sqlalchemy.inspect(engine).has_table(StatisticsMeta.__tablename__)
+                or sqlalchemy.inspect(engine).has_table(Statistics.__tablename__)
+                or sqlalchemy.inspect(engine).has_table(StatisticsRuns.__tablename__)
+                or sqlalchemy.inspect(engine).has_table(
+                    StatisticsShortTerm.__tablename__
+                )
+            ):
+                Base.metadata.drop_all(
+                    bind=engine,
+                    tables=[
+                        StatisticsShortTerm.__table__,
+                        Statistics.__table__,
+                        StatisticsMeta.__table__,
+                        StatisticsRuns.__table__,
+                    ],
+                )
+
+            StatisticsRuns.__table__.create(engine)
+            StatisticsMeta.__table__.create(engine)
+            StatisticsShortTerm.__table__.create(engine)
+            Statistics.__table__.create(engine)
     else:
         raise ValueError(f"No schema migration defined for version {new_version}")
 
diff --git a/homeassistant/components/recorder/models.py b/homeassistant/components/recorder/models.py
index 1c5c9fa90f0..354811bee40 100644
--- a/homeassistant/components/recorder/models.py
+++ b/homeassistant/components/recorder/models.py
@@ -40,7 +40,7 @@ import homeassistant.util.dt as dt_util
 # pylint: disable=invalid-name
 Base = declarative_base()
 
-SCHEMA_VERSION = 21
+SCHEMA_VERSION = 22
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -238,7 +238,7 @@ class StatisticData(TypedDict, total=False):
 class StatisticsBase:
     """Statistics base class."""
 
-    id = Column(Integer, primary_key=True)
+    id = Column(Integer, Identity(), primary_key=True)
     created = Column(DATETIME_TYPE, default=dt_util.utcnow)
 
     @declared_attr
@@ -309,7 +309,7 @@ class StatisticsMeta(Base):  # type: ignore
         {"mysql_default_charset": "utf8mb4", "mysql_collate": "utf8mb4_unicode_ci"},
     )
     __tablename__ = TABLE_STATISTICS_META
-    id = Column(Integer, primary_key=True)
+    id = Column(Integer, Identity(), primary_key=True)
     statistic_id = Column(String(255), index=True)
     source = Column(String(32))
     unit_of_measurement = Column(String(255))
@@ -406,7 +406,7 @@ class StatisticsRuns(Base):  # type: ignore
     """Representation of statistics run."""
 
     __tablename__ = TABLE_STATISTICS_RUNS
-    run_id = Column(Integer, primary_key=True)
+    run_id = Column(Integer, Identity(), primary_key=True)
     start = Column(DateTime(timezone=True))
 
     def __repr__(self) -> str: