diff --git a/pfbudget/db/client.py b/pfbudget/db/client.py
index e911e31..86fb88a 100644
--- a/pfbudget/db/client.py
+++ b/pfbudget/db/client.py
@@ -22,6 +22,9 @@ class DatabaseSession:
             self.__session.commit()
         self.__session.close()
 
+    def close(self):
+        self.__session.close()
+
     def insert(self, sequence: Sequence[Any]) -> None:
         self.__session.add_all(sequence)
 
@@ -33,7 +36,7 @@ class DatabaseSession:
         else:
             stmt = select(what)
 
-        return self.__session.scalars(stmt).all()
+        return self.__session.scalars(stmt).unique().all()
 
 
 class Client:
@@ -50,7 +53,10 @@ class Client:
     T = TypeVar("T")
 
     def select(self, what: Type[T], exists: Optional[Any] = None) -> Sequence[T]:
-        return self.session.select(what, exists)
+        session = self.session
+        result = session.select(what, exists)
+        session.close()
+        return result
 
     def update(self, what: Type[Any], values: Sequence[Mapping[str, Any]]) -> None:
         with self._sessionmaker() as session, session.begin():
diff --git a/pfbudget/db/model.py b/pfbudget/db/model.py
index de4cee4..bb955e5 100644
--- a/pfbudget/db/model.py
+++ b/pfbudget/db/model.py
@@ -65,7 +65,7 @@ class Bank(Base, Export):
     BIC: Mapped[str] = mapped_column(String(8))
     type: Mapped[accounttype]
 
-    nordigen: Mapped[Optional[Nordigen]] = relationship(init=False)
+    nordigen: Mapped[Optional[Nordigen]] = relationship(init=False, lazy="joined")
 
     @property
     def format(self) -> dict[str, Any]:
@@ -101,11 +101,11 @@ class Transaction(Base, Export):
     split: Mapped[bool] = mapped_column(default=False)
 
     category: Mapped[Optional[TransactionCategory]] = relationship(
-        back_populates="transaction", default=None
+        back_populates="transaction", default=None, lazy="joined"
     )
-    tags: Mapped[set[TransactionTag]] = relationship(default_factory=set)
+    tags: Mapped[set[TransactionTag]] = relationship(default_factory=set, lazy="joined")
     note: Mapped[Optional[Note]] = relationship(
-        cascade="all, delete-orphan", passive_deletes=True, default=None
+        cascade="all, delete-orphan", passive_deletes=True, default=None, lazy="joined"
     )
 
     type: Mapped[str] = mapped_column(init=False)
@@ -221,7 +221,7 @@ class TransactionCategory(Base, Export):
     name: Mapped[catfk]
 
     selector: Mapped[CategorySelector] = relationship(
-        cascade="all, delete-orphan", default=Selector_T.unknown
+        cascade="all, delete-orphan", default=Selector_T.unknown, lazy="joined"
     )
 
     transaction: Mapped[Transaction] = relationship(