New project: DatabaseConnection module using OOP principles.

projects/DatabaseConnectionWithOOP/classes.py

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+from abc import ABC, abstractmethod
+import sqlite3
+
+# Abstract Classes 
+class AbstractDatabase(ABC):
+    @abstractmethod
+    def close(self) -> None:
+        pass
+
+# Interfaces
+class I_CommonSelectQueries(ABC):
+    @abstractmethod
+    def execute_simple_select_query(self, table_name:str, fields:list[str]) -> list:
+        pass
+
+class I_CommonTableQueries(ABC):
+    @abstractmethod
+    def create_table(self, table_name:str, fields:list[str]) -> None:
+        pass
+
+
+# Classes
+class Database(AbstractDatabase):
+    def __init__(self, database_name:str) -> None:
+        """
+            Creates an object of Database type, connecting to a simple SQLite3 database.
+
+            Attributes:
+                - database_name (str): Name of the database.
+        """
+        self.__database_name = database_name
+        self.__conn = sqlite3.connect(f'{self.__database_name}.db')
+
+    @property
+    def database_name(self) -> str:
+        return self.__database_name
+
+    @property
+    def conn(self) -> object | None:
+        return self.__conn
+
+    def close(self):
+        """
+            Closes database connection.
+        """ 
+        self.conn.close()
+
+class Cursor():
+    def __init__(self, database_object:Database) -> None:
+        """
+            Creates a cursor object in base of the received database_object as parameter.
+
+            Attributes:
+                - database_object (Database): Database connection object to create the cursor.
+        """
+        self.database = database_object
+        self.__cursor = self.database.conn.cursor()
+
+    @property
+    def cursor(self) -> object:
+        return self.__cursor
+
+    def execute_query(self, query:str) -> list | None:
+        """
+            The Cursor object executes an SQL query that the user will pass as str, for example 'SELECT * FROM Users WHERE age > 21'.
+
+            Attributes:
+                - query (str): The query that will be executed, it can be of any type (SELECT, UPDATE, DELETE, INSERT, etc.).
+        """
+        try:
+            result = self.cursor.execute(query)
+            print('Query was executed.')
+            return result.fetchall() if result else []
+        except Exception as e:
+            print('Impossible to execute the query:', e)
+            return None 
+
+# Custom cursor for most common queries execution.
+class CustomCursor(Cursor, I_CommonTableQueries, I_CommonSelectQueries):
+    def __init__(self, database_object:Database):
+        super().__init__(database_object)
+
+    def execute_query(self, query:str):
+        """
+            Executes a simple query of any type wether SELECT, INSERT, CREATE TABLE, DELETE, etc.
+            This method leverages its class's parent class method with the same name, behavior and attributes.
+
+            Attributes:
+                - query (str): The query that will be executed.
+        """
+        return super().execute_query(query)
+
+    def execute_simple_select_query(self, table_name:str, fields:list[str]) -> list:
+        """
+            Executes a simple query of SELECT type with the fields to show provided as parameters and the name of the table.
+
+            Attributes:
+                - table_name (str): Name of the table from where data is going to be obtained.
+                - fields (list[str]): List of fields to fetch from the database's table.
+
+            Return:
+                - data (list): List of rows obtained from the SELECT query in str format.
+        """
+        query = f"""SELECT {', '.join(fields)} FROM {table_name};"""
+        data = self.execute_query(query)
+        return data
+
+    def create_table(self, table_name:str, fields:list[str]) -> None:
+        """
+            Creates a table on the database based on the provided fields and table name.
+
+            Attributes:
+                - table_name (): Name of the table that is going to be created.
+                -fields (list): List of the table fields in string format. 
+
+            Return:
+                - None
+        """
+
+        # Format the fields from fields list in a single string
+        formated_fields = ', '.join(fields)
+
+        query = f"""CREATE TABLE IF NOT EXISTS {table_name} ({formated_fields})"""
+        self.execute_query(query)
+
+    def insert_rows(self, table_name:str, fields:list[str], values:list[list[str]]) -> bool:
+        """
+            Executes a classic INSERT query receiving the name of the fields matching the values to insert and the name of the table
+            This method iterates over every row on the provided list of values to make an insertion on the database in the table..
+
+            Attributes:
+                - table_name (str): Name of the table where the data will be inserted as a new row.
+                - fields (list[str]): List of fields to determine which type of data should be inserted.
+                - values (list[list[str]]): List of rows to insert, every row is a list of every value in the desired format.  
+
+            Return:
+                - succes (str): True if rows were inserted. False if it was not possible to insert rows.
+        """
+        formated_fields = ', '.join(fields)
+        rows_list = values
+        for row in rows_list:
+            try:
+                formated_values = ', '.join(f"'{value}'" for value in row)
+                query = f"""INSERT INTO {table_name} ({formated_fields}) VALUES({formated_values});"""
+                self.execute_query(query)
+            except Exception as e:
+                print(f'Error during inserting data into database on table {table_name}:', e)
+                succes = False
+        succes = True
+        return succes

projects/DatabaseConnectionWithOOP/main.py

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+from classes import Database, CustomCursor
+
+
+""" Now with a simple cursor object we can execute the most common queries like the typical 'SELECT', or create a table with ease reducing the SQL statement we have to provide to just parameters. """
+my_database = Database('MyDatabase')
+my_cursor = CustomCursor(my_database)
+
+# Creating users table
+my_cursor.create_table('users', ['id INTEGER PRIMARY KEY AUTOINCREMENT', 'username TEXT UNIQUE NOT NULL', 'email TEXT UNIQUE NOT NULL', 'password TEXT NOT NULL', 'age INTEGER'])
+
+# Inserting data in users table
+users_to_insert = [
+    ['Joaquin', '[email protected]', '123password', 22], 
+    ['Aline', '[email protected]', '123password', 21], 
+    ['Henry', '[email protected]', '123password', 35], 
+    ['James', '[email protected]', '123password', 32], 
+    ['Nicole', '[email protected]', '123password', 28],
+    ['Maria', '[email protected]', '123password', 38] 
+]
+users_fields = ['username', 'email', 'password', 'age']
+my_cursor.insert_rows('users', users_fields, users_to_insert)
+
+# Fetching data from database in users table
+result = my_cursor.execute_simple_select_query('users', users_fields)
+result2 = my_cursor.execute_simple_select_query('users', ['username', 'age'])
+print('First fetch:', result)
+print('Second fetch:', result2)

projects/DatabaseConnectionWithOOP/requirements.txt

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+aiohappyeyeballs==2.4.6
+aiohttp==3.11.12
+aiosignal==1.3.2
+annotated-types==0.7.0
+anyio==4.8.0
+asgiref==3.8.1
+attrs==25.1.0
+blinker==1.9.0
+certifi==2024.8.30
+chardet==5.2.0
+charset-normalizer==3.4.0
+click==8.1.8
+colorama==0.4.6
+Deprecated==1.2.15
+dj-database-url==2.3.0
+Django==5.1.6
+django-environ==0.12.0
+django-oauth2-provider==0.2.6.1
+django-redis==5.4.0
+djangorestframework==3.15.2
+djangorestframework-oauth==1.1.0
+djangorestframework_simplejwt==5.4.0
+drf-yasg==1.21.9
+fastapi==0.115.6
+Flask==3.1.0
+frozenlist==1.5.0
+h11==0.14.0
+idna==3.10
+inflection==0.5.1
+itsdangerous==2.2.0
+Jinja2==3.1.5
+limits==4.0.0
+MarkupSafe==3.0.2
+multidict==6.1.0
+packaging==24.2
+pillow==11.1.0
+prettytable==3.14.0
+propcache==0.2.1
+psutil==7.0.0
+psycopg2==2.9.10
+psycopg2-binary==2.9.10
+pydantic==2.10.5
+pydantic_core==2.27.2
+PyDirectInput==1.0.4
+PyJWT==2.10.1
+pynput==1.7.7
+python-dotenv==1.0.1
+python-magic==0.4.27
+python-magic-bin==0.4.14
+pytz==2025.1
+PyYAML==6.0.2
+redis==5.2.1
+reportlab==4.3.1
+requests==2.32.3
+shortuuid==1.0.13
+six==1.17.0
+slowapi==0.1.9
+sniffio==1.3.1
+sqlparse==0.5.3
+starlette==0.41.3
+translation==1.0.5
+typing_extensions==4.12.2
+tzdata==2025.1
+uritemplate==4.1.1
+urllib3==2.2.3
+uvicorn==0.34.0
+wcwidth==0.2.13
+Werkzeug==3.1.3
+wrapt==1.17.2
+yarl==1.18.3