{"id":90,"date":"2025-10-25T06:50:45","date_gmt":"2025-10-25T06:50:45","guid":{"rendered":"https:\/\/codetypingpro.com\/?p=90"},"modified":"2025-12-17T07:49:13","modified_gmt":"2025-12-17T07:49:13","slug":"lesson-23-database-connectivity-in-python","status":"publish","type":"post","link":"https:\/\/codetypingpro.com\/?p=90","title":{"rendered":"Lesson 23: Database Connectivity in Python"},"content":{"rendered":"\n

<\/h2>\n\n\n\n

\ud83c\udfaf Lesson Objective<\/strong><\/h3>\n\n\n\n

To understand how to connect Python with a database, perform CRUD operations (Create, Read, Update, Delete), and handle data efficiently using the sqlite3<\/code> module.<\/p>\n\n\n\n

\n\n\n\n

\ud83e\udde9 1. What Is Database Connectivity?<\/strong><\/h2>\n\n\n\n

Database connectivity allows a Python program to:<\/p>\n\n\n\n

    \n
  • Connect to a database (like SQLite, MySQL, PostgreSQL)<\/li>\n\n\n\n
  • Execute SQL queries<\/li>\n\n\n\n
  • Store, retrieve, and manage structured data<\/li>\n<\/ul>\n\n\n\n

    Python provides a built-in module called sqlite3<\/code><\/strong> that works with SQLite<\/strong> \u2014 a lightweight database stored in a single file.<\/p>\n\n\n\n

    \n\n\n\n

    \u2699\ufe0f 2. Importing the sqlite3<\/code> Module<\/strong><\/h2>\n\n\n\n
    import sqlite3\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \ud83e\uddf1 3. Connecting to a Database<\/strong><\/h2>\n\n\n\n
    import sqlite3\n\nconn = sqlite3.connect(\"students.db\")  # Creates a database file\nprint(\"Database connected successfully!\")\nconn.close()\n<\/code><\/pre>\n\n\n\n
    Output:<\/strong><\/p>\n\n\n\n
    Database connected successfully!\n<\/code><\/pre>\n\n\n\n
    \u2705 If the file doesn\u2019t exist, it will be automatically created.<\/p>\n\n\n\n
    \n\n\n\n
    \ud83e\uddf0 4. Creating a Table<\/strong><\/h2>\n\n\n\n
    import sqlite3\n\nconn = sqlite3.connect(\"students.db\")\ncursor = conn.cursor()\n\ncursor.execute(\"\"\"\nCREATE TABLE IF NOT EXISTS students (\n    id INTEGER PRIMARY KEY AUTOINCREMENT,\n    name TEXT,\n    age INTEGER,\n    grade TEXT\n)\n\"\"\")\n\nprint(\"Table created successfully!\")\nconn.commit()\nconn.close()\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \ud83d\udcdd 5. Inserting Data into Table<\/strong><\/h2>\n\n\n\n
    conn = sqlite3.connect(\"students.db\")\ncursor = conn.cursor()\n\ncursor.execute(\"INSERT INTO students (name, age, grade) VALUES (?, ?, ?)\", \n               (\"Ali\", 20, \"A\"))\ncursor.execute(\"INSERT INTO students (name, age, grade) VALUES (?, ?, ?)\", \n               (\"Sara\", 21, \"B\"))\n\nconn.commit()\nprint(\"Data inserted successfully!\")\nconn.close()\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \ud83d\udcd6 6. Reading (Fetching) Data<\/strong><\/h2>\n\n\n\n
    conn = sqlite3.connect(\"students.db\")\ncursor = conn.cursor()\n\ncursor.execute(\"SELECT * FROM students\")\nrows = cursor.fetchall()\n\nfor row in rows:\n    print(row)\n\nconn.close()\n<\/code><\/pre>\n\n\n\n
    Output:<\/strong><\/p>\n\n\n\n
    (1, 'Ali', 20, 'A')\n(2, 'Sara', 21, 'B')\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \u270f\ufe0f 7. Updating Data<\/strong><\/h2>\n\n\n\n
    conn = sqlite3.connect(\"students.db\")\ncursor = conn.cursor()\n\ncursor.execute(\"UPDATE students SET grade = ? WHERE name = ?\", (\"A+\", \"Sara\"))\n\nconn.commit()\nprint(\"Record updated successfully!\")\nconn.close()\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \u274c 8. Deleting Data<\/strong><\/h2>\n\n\n\n
    conn = sqlite3.connect(\"students.db\")\ncursor = conn.cursor()\n\ncursor.execute(\"DELETE FROM students WHERE name = ?\", (\"Ali\",))\n\nconn.commit()\nprint(\"Record deleted successfully!\")\nconn.close()\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \ud83d\udd10 9. Using with<\/code> Statement (Auto-Close Connection)<\/strong><\/h2>\n\n\n\n
    import sqlite3\n\nwith sqlite3.connect(\"students.db\") as conn:\n    cursor = conn.cursor()\n    cursor.execute(\"SELECT * FROM students\")\n    print(cursor.fetchall())\n<\/code><\/pre>\n\n\n\n
    \u2705 Using with<\/code> automatically commits changes and closes the connection.<\/p>\n\n\n\n
    \n\n\n\n
    \ud83d\udca1 10. Real-Life Example \u2013 Employee Database<\/strong><\/h2>\n\n\n\n
    import sqlite3\n\ndef create_table():\n    conn = sqlite3.connect(\"company.db\")\n    cursor = conn.cursor()\n    cursor.execute(\"\"\"\n    CREATE TABLE IF NOT EXISTS employees (\n        id INTEGER PRIMARY KEY AUTOINCREMENT,\n        name TEXT,\n        department TEXT,\n        salary REAL\n    )\n    \"\"\")\n    conn.commit()\n    conn.close()\n\ndef insert_employee(name, department, salary):\n    conn = sqlite3.connect(\"company.db\")\n    cursor = conn.cursor()\n    cursor.execute(\"INSERT INTO employees (name, department, salary) VALUES (?, ?, ?)\",\n                   (name, department, salary))\n    conn.commit()\n    conn.close()\n\ndef view_employees():\n    conn = sqlite3.connect(\"company.db\")\n    cursor = conn.cursor()\n    cursor.execute(\"SELECT * FROM employees\")\n    for row in cursor.fetchall():\n        print(row)\n    conn.close()\n\n# Usage\ncreate_table()\ninsert_employee(\"Sameer\", \"IT\", 75000)\ninsert_employee(\"Aisha\", \"HR\", 50000)\nview_employees()\n<\/code><\/pre>\n\n\n\n
    Output:<\/strong><\/p>\n\n\n\n
    (1, 'Sameer', 'IT', 75000.0)\n(2, 'Aisha', 'HR', 50000.0)\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \ud83d\udce6 11. Using Pandas with SQLite<\/strong><\/h2>\n\n\n\n
    You can also read data directly into a DataFrame.<\/p>\n\n\n\n
    import pandas as pd\nimport sqlite3\n\nconn = sqlite3.connect(\"company.db\")\ndf = pd.read_sql_query(\"SELECT * FROM employees\", conn)\nprint(df)\nconn.close()\n<\/code><\/pre>\n\n\n\n
    Output:<\/strong><\/p>\n\n\n\n
       id    name department   salary\n0   1  Sameer        IT  75000.0\n1   2   Aisha        HR  50000.0\n<\/code><\/pre>\n\n\n\n
    <\/p>\n","protected":false},"excerpt":{"rendered":"
    \ud83c\udfaf Lesson Objective To understand how to connect Python with a database, perform CRUD operations (Create, Read, Update, Delete), and handle data efficiently using the sqlite3 module. \ud83e\udde9 1. What Is Database Connectivity? Database connectivity allows a Python program to: Python provides a built-in module called sqlite3 that works with SQLite \u2014 a lightweight database […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6,1],"tags":[],"class_list":["post-90","post","type-post","status-publish","format-standard","hentry","category-python-easy-course-outline","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/posts\/90","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=90"}],"version-history":[{"count":1,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/posts\/90\/revisions"}],"predecessor-version":[{"id":91,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/posts\/90\/revisions\/91"}],"wp:attachment":[{"href":"https:\/\/codetypingpro.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=90"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=90"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=90"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}