diff --git a/db.sqlite b/db.sqlite
index 6108c74..659559a 100644
Binary files a/db.sqlite and b/db.sqlite differ
diff --git a/library_backend/database.py b/library_backend/database.py
index 8297b01..9943901 100644
--- a/library_backend/database.py
+++ b/library_backend/database.py
@@ -1,5 +1,8 @@
 import random
+import sqlalchemy
 import uuid
+
+
 from datetime import date
 from functools import wraps
 from faker import Faker
@@ -39,6 +42,7 @@ def __init__(self):
         self.engine = create_engine("sqlite:///db.sqlite", echo=False)
         self.session = None
         self.connection_name = None
+        self.inspect = sqlalchemy.inspect(self.engine)
 
     def __enter__(self):
         self.session = sessionmaker(bind=self.engine)()
@@ -46,9 +50,9 @@ def __enter__(self):
     @check_session()
     def create_tables_if_not_exists(self):
         try:
-            if not (self.engine.dialect.has_table(self.engine, UsersDBModel.__tablename__)
-                    and self.engine.dialect.has_table(self.engine, BooksDBModel.__tablename__)
-                    and self.engine.dialect.has_table(self.engine, ReservationsDBModel.__tablename__)):
+            if not (self.inspect.has_table(UsersDBModel.__tablename__, schema=None)
+                    and self.inspect.has_table(BooksDBModel.__tablename__, schema=None)
+                    and self.inspect.has_table(ReservationsDBModel.__tablename__, schema=None)):
                 logger.info(f"Creating table {UsersDBModel.__tablename__}...")
                 try:
                     Base.metadata.create_all(self.engine)
diff --git a/requirements.txt b/requirements.txt
index b203acf..9f0967f 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,5 @@
-flask
-sqlalchemy
-faker
-pytest
+mock==4.0.3
+flask==2.3.2
+sqlalchemy==1.4.35
+faker==13.3.4
+pytest==7.11.1
diff --git a/tests/books_endpoints/test_book_service.py b/tests/books_endpoints/test_book_service.py
index 91d6d1b..6a4218a 100644
--- a/tests/books_endpoints/test_book_service.py
+++ b/tests/books_endpoints/test_book_service.py
@@ -1,8 +1,9 @@
 import copy
 
-import mock
 import pytest
 
+from unittest import mock
+
 from library_backend.exceptions import BookAlreadyExists, ResourceNotFound
 from library_backend.service import BookService, BooksDBModel