Connect SQLite with Python

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To connect SQLite with Python, you can use the built-in sqlite3 module in Python. Here are the steps:

  1. Import the sqlite3 module:

    To connect SQLite with Python, you can use the built-in sqlite3 module in Python. Here are the steps:

import sqlite3

2. Connect to the SQLite database:

conn = sqlite3.connect('database.db')

Replace 'database.db' with the name of your SQLite database file. If the database file does not exist, SQLite will create it for you.

3. Create a cursor object:

cursor = conn.cursor()

4. Execute SQL commands using the cursor:

cursor.execute("CREATE TABLE my_table (id INTEGER PRIMARY KEY, name TEXT)")
cursor.execute("INSERT INTO my_table (name) VALUES ('John')")
cursor.execute("SELECT * FROM my_table")
rows = cursor.fetchall()
print(rows)

The above code creates a table named my_table with two columns (id and name), inserts a row with the name “John”, selects all rows from the table, and prints the result.

5. Commit the changes and close the connection:

conn.commit()
conn.close()
  1. It’s important to commit the changes before closing the connection, so that the changes are saved to the database.

That’s it! You now know how to connect to a SQLite database and execute SQL commands in Python using the sqlite3 module.

Install Python:

To install Python on your computer, follow these steps:

  1. Go to the official Python website at https://www.python.org/ and click on the “Downloads” tab.
  2. Choose the appropriate version of Python for your operating system. Python is available for Windows, Mac OS, and Linux.
  3. Download the installer for the latest stable version of Python. You can either download the 32-bit or 64-bit version of Python depending on your system architecture.
  4. Run the installer and follow the installation instructions. You will be prompted to choose the installation directory and customize the installation options, but you can usually leave the default settings.
  5. Once the installation is complete, open the terminal (or command prompt) and type python to check that Python is installed correctly. If Python is installed correctly, you will see the Python version number and a command prompt that looks like >>>.

Congratulations! You have successfully installed Python on your computer.

Install SQLite:

To install SQLite on your computer, follow these steps:

  1. Go to the official SQLite website at https://www.sqlite.org/index.html and click on the “Download” link in the top menu.
  2. Scroll down to the “Precompiled Binaries for Windows” section (or the equivalent section for your operating system), and download the appropriate binary file for your system. There are several versions available, including DLL files, command-line tools, and GUI tools.
  3. Extract the contents of the downloaded file to a directory on your computer. You can choose any directory you like, but make sure you remember the location.
  4. Add the SQLite directory to your system’s PATH environment variable. This will allow you to use the SQLite command-line tool from any directory on your computer. To do this, follow these steps:
    • Right-click on “This PC” (or “My Computer”) and select “Properties”.
    • Click on “Advanced system settings” and then click on the “Environment Variables” button.
    • Under “System Variables”, find the “Path” variable and click on “Edit”.
    • Click on “New” and add the path to the directory where you extracted SQLite.
    • Click “OK” to close all the windows.
  5. To verify that SQLite is installed correctly, open a command prompt (or terminal) and type sqlite3. You should see the SQLite command-line prompt, which looks like sqlite>.

Congratulations! You have successfully installed SQLite on your computer.

Create a table:

To create a table in a SQLite database, you can use the SQL CREATE TABLE statement. Here’s an example:

CREATE TABLE my_table (
    id INTEGER PRIMARY KEY,
    name TEXT,
    age INTEGER
);

This statement creates a table called my_table with three columns: id, name, and age. The id column is defined as an INTEGER and marked as the primary key. The name column is defined as a TEXT, and the age column is defined as an INTEGER.

You can execute this SQL statement using a SQLite client or a programming language that supports SQLite, such as Python. Here’s an example of how to create this table in Python using the sqlite3 module:

import sqlite3

conn = sqlite3.connect('my_database.db')
cursor = conn.cursor()

cursor.execute('''CREATE TABLE my_table (
                id INTEGER PRIMARY KEY,
                name TEXT,
                age INTEGER
                )''')

conn.commit()
conn.close()

This code connects to a SQLite database called my_database.db, creates a cursor object, executes the CREATE TABLE statement to create the my_table table, commits the changes, and closes the connection.

You can customize this SQL statement to create a table with the columns and data types that you need for your application.

Insert Records:

To insert records into a SQLite database table, you can use the SQL INSERT INTO statement. Here’s an example:

INSERT INTO my_table (name, age) VALUES ('Alice', 25);

This statement inserts a new record into the my_table table with the values ‘Alice’ and 25 for the name and age columns, respectively.

You can execute this SQL statement using a SQLite client or a programming language that supports SQLite, such as Python. Here’s an example of how to insert a record into the my_table table in Python using the sqlite3 module:

import sqlite3

conn = sqlite3.connect('my_database.db')
cursor = conn.cursor()

# insert a new record
cursor.execute("INSERT INTO my_table (name, age) VALUES (?, ?)", ('Alice', 25))

conn.commit()
conn.close()

This code connects to a SQLite database called my_database.db, creates a cursor object, executes the INSERT INTO statement to insert a new record into the my_table table, using parameter substitution to avoid SQL injection vulnerabilities, commits the changes, and closes the connection.

You can customize this SQL statement to insert records with the values that you need for your application. If you want to insert multiple records at once, you can use a single INSERT INTO statement with multiple value sets, separated by commas.

Select Records:

To select records from a SQLite database table, you can use the SQL SELECT statement. Here’s an example:

SELECT * FROM my_table;

This statement selects all records from the my_table table and returns all columns (*).

You can execute this SQL statement using a SQLite client or a programming language that supports SQLite, such as Python. Here’s an example of how to select records from the my_table table in Python using the sqlite3 module:

import sqlite3

conn = sqlite3.connect('my_database.db')
cursor = conn.cursor()

# select all records
cursor.execute("SELECT * FROM my_table")

rows = cursor.fetchall()

for row in rows:
    print(row)

conn.close()

This code connects to a SQLite database called my_database.db, creates a cursor object, executes the SELECT statement to select all records from the my_table table, retrieves the selected rows using the fetchall() method, and prints the selected rows.

You can customize this SQL statement to select specific columns or apply filters using the WHERE clause. If you want to select a limited number of rows, you can use the LIMIT clause.