Using PyQt to Retrieve Data from a QTableWidget and Save it to a Database

PyQt is a set of Python bindings for the Qt application framework and runs on all platforms supported by Qt including Windows, MacOS, iOS, and Android. It is widely used for creating desktop applications with a modern and user-friendly interface. In this tutorial, we will learn how to read data from a QTableWidget in PyQt and insert it into a database using SQLite.

Let’s start by creating a PyQt application with a QTableWidget and a QPushButton. The QTableWidget will display some data, and the QPushButton will allow us to read this data and insert it into a database.

import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QTableWidget, QTableWidgetItem, QPushButton, QVBoxLayout, QWidget
import sqlite3

class MyWindow(QMainWindow):
    def __init__(self):
        super().__init__()

        self.setGeometry(100, 100, 600, 400) 
        self.setWindowTitle("PyQt Read Data From QTableWidget and Insert Into Database")

        self.table = QTableWidget()
        self.table.setColumnCount(2)
        self.table.setHorizontalHeaderLabels(['Name', 'Age'])

        self.button = QPushButton("Insert Data Into Database")
        self.button.clicked.connect(self.insert_data_into_database)

        layout = QVBoxLayout()
        layout.addWidget(self.table)
        layout.addWidget(self.button)

        container = QWidget()
        container.setLayout(layout)

        self.setCentralWidget(container)

    def insert_data_into_database(self):
        conn = sqlite3.connect('data.db')
        c = conn.cursor()

        c.execute("CREATE TABLE IF NOT EXISTS users (name TEXT, age INTEGER)")

        for row in range(self.table.rowCount()):
            name = self.table.item(row, 0).text()
            age = int(self.table.item(row, 1).text())

            c.execute("INSERT INTO users (name, age) VALUES (?, ?)", (name, age))

        conn.commit()
        conn.close()

        print("Data inserted into database")

if __name__ == "__main__":
    app = QApplication(sys.argv)
    window = MyWindow()
    window.show()
    sys.exit(app.exec_())

In this code snippet, we create a PyQt application with a main window that contains a QTableWidget and a QPushButton. We set up the layout using QVBoxLayout and add the widgets to the layout. The QPushButton is connected to a method called insert_data_into_database. Inside this method, we establish a connection to a SQLite database named data.db, create a table named users if it doesn’t exist, and then loop through the rows of the QTableWidget to fetch the data in each cell and insert it into the database.

To run this code, save it in a file named main.py and run it using the following command:

python main.py

Now, let’s add some data to the QTableWidget in our PyQt application. We can do this by adding a few lines of code in the MyWindow class:

    def __init__(self):
        super().__init__()

        self.setGeometry(100, 100, 600, 400)
        self.setWindowTitle("PyQt Read Data From QTableWidget and Insert Into Database")

        self.table = QTableWidget()
        self.table.setColumnCount(2)
        self.table.setHorizontalHeaderLabels(['Name', 'Age'])

        data = [['Alice', '25'], ['Bob', '30'], ['Charlie', '35']]

        for i, (name, age) in enumerate(data):
            self.table.insertRow(i)
            self.table.setItem(i, 0, QTableWidgetItem(name))
            self.table.setItem(i, 1, QTableWidgetItem(age))

        self.button = QPushButton("Insert Data Into Database")
        self.button.clicked.connect(self.insert_data_into_database)

        layout = QVBoxLayout()
        layout.addWidget(self.table)
        layout.addWidget(self.button)

        container = QWidget()
        container.setLayout(layout)

        self.setCentralWidget(container)

Now, when you run the application, you will see the data displayed in the QTableWidget. Clicking the "Insert Data Into Database" button will insert this data into the SQLite database.

That’s it! You have successfully learned how to read data from a QTableWidget in PyQt and insert it into a database using SQLite. PyQt is a powerful framework for creating desktop applications with Python, and it provides a wide range of tools for creating interactive and user-friendly interfaces. If you have any questions or run into any issues, feel free to ask for help in the comments. Happy coding!