db: add composite indexes and merge-user optimizations

db/dal/user_dal.py

@@ -629,23 +629,22 @@ async def get_user_ids_without_active_subscription(session: AsyncSession) -> Lis
     from datetime import datetime, timezone
     now = datetime.now(timezone.utc)
 
-    # Subquery for users with active subscription
-    active_subs_subq = (
-        select(Subscription.user_id)
-        .where(
-            and_(
-                Subscription.is_active == True,
-                Subscription.end_date > now,
-            )
-        )
-    ).scalar_subquery()
+    active_subs = aliased(Subscription)
 
     stmt = (
         select(User.user_id)
+        .outerjoin(
+            active_subs,
+            and_(
+                active_subs.user_id == User.user_id,
+                active_subs.is_active == True,
+                active_subs.end_date > now,
+            ),
+        )
         .where(
             and_(
                 User.is_banned == False,
-                ~User.user_id.in_(active_subs_subq),
+                active_subs.user_id.is_(None),
             )
         )
     )

db/database_setup.py

@@ -20,6 +20,8 @@ def init_db_connection(settings: Settings) -> sessionmaker:
             settings.DATABASE_URL,
             echo=False,
             pool_pre_ping=True,
+            pool_size=20,
+            max_overflow=10,
         )
 
     local_async_session_factory = async_sessionmaker(

db/migrator.py

@@ -251,6 +251,64 @@ def _migration_0007_add_telegram_photo_url(connection: Connection) -> None:
     )
 
 
+def _migration_0008_add_email_verification_code_status(connection: Connection) -> None:
+    inspector = inspect(connection)
+    columns: Set[str] = {col["name"] for col in inspector.get_columns("email_verification_codes")}
+
+    if "status" not in columns:
+        connection.execute(
+            text(
+                "ALTER TABLE email_verification_codes ADD COLUMN status VARCHAR NOT NULL DEFAULT 'active'"
+            )
+        )
+    else:
+        connection.execute(
+            text(
+                """
+                UPDATE email_verification_codes
+                SET status = 'active'
+                WHERE status IS NULL OR status = ''
+                """
+            )
+        )
+
+    connection.execute(
+        text(
+            """
+            CREATE INDEX IF NOT EXISTS ix_email_verification_codes_status
+            ON email_verification_codes (status)
+            """
+        )
+    )
+
+
+def _migration_0009_add_composite_indexes(connection: Connection) -> None:
+    connection.execute(
+        text(
+            """
+            CREATE INDEX IF NOT EXISTS ix_subscriptions_is_active_end_date
+            ON subscriptions (is_active, end_date)
+            """
+        )
+    )
+    connection.execute(
+        text(
+            """
+            CREATE INDEX IF NOT EXISTS ix_subscriptions_user_id_is_active
+            ON subscriptions (user_id, is_active)
+            """
+        )
+    )
+    connection.execute(
+        text(
+            """
+            CREATE INDEX IF NOT EXISTS ix_payments_user_id_status
+            ON payments (user_id, status)
+            """
+        )
+    )
+
+
 MIGRATIONS: List[Migration] = [
     Migration(
         id="0001_add_channel_subscription_fields",
@@ -287,6 +345,16 @@ MIGRATIONS: List[Migration] = [
         description="Store Telegram profile photo URLs for linked users",
         upgrade=_migration_0007_add_telegram_photo_url,
     ),
+    Migration(
+        id="0008_add_email_verification_code_status",
+        description="Track superseded email verification codes explicitly",
+        upgrade=_migration_0008_add_email_verification_code_status,
+    ),
+    Migration(
+        id="0009_add_composite_indexes",
+        description="Add composite indexes for subscription and payment lookups",
+        upgrade=_migration_0009_add_composite_indexes,
+    ),
 ]
 
 

db/models.py

@@ -1,4 +1,4 @@
-from sqlalchemy import create_engine, Column, Integer, String, Boolean, DateTime, Float, ForeignKey, UniqueConstraint, Text, BigInteger
+from sqlalchemy import create_engine, Column, Integer, String, Boolean, DateTime, Float, ForeignKey, UniqueConstraint, Text, BigInteger, Index
 from sqlalchemy.orm import relationship, DeclarativeBase
 from sqlalchemy.ext.asyncio import AsyncAttrs
 from sqlalchemy.sql import func
@@ -61,6 +61,10 @@ class User(Base):
 
 class Subscription(Base):
     __tablename__ = "subscriptions"
+    __table_args__ = (
+        Index("ix_subscriptions_is_active_end_date", "is_active", "end_date"),
+        Index("ix_subscriptions_user_id_is_active", "user_id", "is_active"),
+    )
 
     subscription_id = Column(Integer, primary_key=True, autoincrement=True)
     user_id = Column(BigInteger,
@@ -105,6 +109,7 @@ class EmailVerificationCode(Base):
     )
     expires_at = Column(DateTime(timezone=True), nullable=False, index=True)
     consumed_at = Column(DateTime(timezone=True), nullable=True)
+    status = Column(String, nullable=False, default="active", index=True)
     attempts = Column(Integer, nullable=False, default=0)
     created_at = Column(DateTime(timezone=True), server_default=func.now())
 
@@ -131,6 +136,9 @@ class SecurityThrottle(Base):
 
 class Payment(Base):
     __tablename__ = "payments"
+    __table_args__ = (
+        Index("ix_payments_user_id_status", "user_id", "status"),
+    )
 
     payment_id = Column(Integer, primary_key=True, autoincrement=True)
     user_id = Column(BigInteger,