Data integrity checks in Testing Fundamentals - Test Execution Trace

Test Overview

This test verifies that data saved in a database remains accurate and unchanged after a save operation. It checks if the data retrieved matches the data input, ensuring data integrity.

Test Code - unittest

Testing Fundamentals

import unittest

class TestDataIntegrity(unittest.TestCase):
    def setUp(self):
        # Simulate a simple in-memory database as a dictionary
        self.database = {}

    def save_data(self, key, value):
        # Simulate saving data
        self.database[key] = value

    def get_data(self, key):
        # Simulate retrieving data
        return self.database.get(key, None)

    def test_data_integrity_after_save(self):
        input_data = {'id': 1, 'name': 'Alice', 'age': 30}
        self.save_data(input_data['id'], input_data)
        retrieved_data = self.get_data(input_data['id'])
        self.assertEqual(retrieved_data, input_data, "Data retrieved does not match data saved")

if __name__ == '__main__':
    unittest.main()

Execution Trace - 5 Steps

Step	Action	System State	Assertion	Result
1	Test starts and setUp method initializes an empty in-memory database	Empty dictionary simulating database: {}	-	PASS
2	Test calls save_data with key=1 and value={'id':1, 'name':'Alice', 'age':30}	Database now contains: {1: {'id':1, 'name':'Alice', 'age':30}}	-	PASS
3	Test calls get_data with key=1 to retrieve saved data	Retrieved data is {'id':1, 'name':'Alice', 'age':30}	Check if retrieved data equals input data	PASS
4	Assertion compares retrieved data with input data	Both data sets match exactly	assertEqual passes confirming data integrity	PASS
5	Test ends successfully	No errors, test passed	-	PASS

Failure Scenario

Failing Condition: Data retrieved from the database does not match the data saved (e.g., data corruption or incorrect save)

Execution Trace Quiz - 3 Questions

What does the test verify after saving data?

A That the data is deleted after saving

B That the database is empty

C That the data retrieved matches the data saved

D That the data is saved twice

Key Result

Always verify that data retrieved after saving matches exactly what was saved to ensure data integrity and catch any corruption or unintended changes.