Stored procedure testing in Testing Fundamentals - Test Execution Trace

Test Overview

This test runs a stored procedure that calculates the total sales for a given product ID. It verifies that the procedure returns the correct total amount.

Test Code - PyTest

Testing Fundamentals

import pyodbc
import unittest

class TestStoredProcedure(unittest.TestCase):
    def setUp(self):
        self.conn = pyodbc.connect('DRIVER={SQL Server};SERVER=localhost;DATABASE=SalesDB;Trusted_Connection=yes;')
        self.cursor = self.conn.cursor()

    def tearDown(self):
        self.cursor.close()
        self.conn.close()

    def test_total_sales_procedure(self):
        product_id = 101
        # Execute stored procedure
        self.cursor.execute("EXEC CalculateTotalSales ?", product_id)
        result = self.cursor.fetchone()
        self.assertIsNotNone(result, "No result returned from stored procedure")
        total_sales = result[0]
        # Expected total sales for product_id 101 is 1500.00
        self.assertEqual(total_sales, 1500.00, f"Total sales for product {product_id} should be 1500.00")

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

Execution Trace - 6 Steps

Step	Action	System State	Assertion	Result
1	Test starts	Test framework initializes test case for stored procedure	—	PASS
2	Database connection opens using pyodbc	Connected to SalesDB on localhost	—	PASS
3	Stored procedure 'CalculateTotalSales' is executed with product_id=101	Procedure runs on database server	—	PASS
4	Fetch the result from stored procedure execution	Result row with total sales value retrieved	Check that result is not None	PASS
5	Assert that total sales equals 1500.00	Compare returned value with expected	total_sales == 1500.00	PASS
6	Close database connection and end test	Resources released	—	PASS

Failure Scenario

Failing Condition: Stored procedure returns no result or incorrect total sales value

Execution Trace Quiz - 3 Questions

What does the test verify after executing the stored procedure?

A That the stored procedure returns the correct total sales value

B That the database connection is closed

C That the product ID is valid

D That the stored procedure runs without errors

Key Result

Always verify that stored procedures return expected results by asserting on their output values, and ensure test data in the database matches expected conditions.

Practice

1. What is the main purpose of testing a stored procedure in a database?

easy

A. To verify that the procedure performs the expected operations correctly

B. To create new tables in the database

C. To delete all data from the database

D. To change the database schema automatically

Solution

1. Step 1: Understand stored procedure testing goal

   Testing stored procedures means checking if they do what they are supposed to do.

2. Step 2: Identify correct purpose

   Creating tables, deleting data, or changing schema are not testing goals but database operations.

3. Final Answer:

   To verify that the procedure performs the expected operations correctly -> Option A

4. Quick Check:

   Testing = Verify expected operations [OK]

Hint: Testing checks if procedure works as expected [OK]

Common Mistakes:

• Confusing testing with creating or deleting data
• Thinking testing changes database structure
• Assuming testing runs automatically without checks

2. Which SQL command is used to execute a stored procedure named GetUserData with an input parameter userId?

easy

A. EXECUTE GetUserData userId;

B. RUN PROCEDURE GetUserData userId;

C. START GetUserData(userId);

D. CALL GetUserData(userId);

Solution

1. Step 1: Recall correct syntax for calling stored procedures

   The standard SQL command to run a stored procedure is CALL procedure_name(parameters);

2. Step 2: Match syntax with options

   Only CALL GetUserData(userId); uses CALL with parentheses and parameter correctly.

3. Final Answer:

   CALL GetUserData(userId); -> Option D

4. Quick Check:

   CALL + procedure + (params) = correct call [OK]

Hint: Use CALL with parentheses to run procedures [OK]

Common Mistakes:

• Using EXECUTE without parentheses
• Using RUN PROCEDURE which is invalid syntax
• Forgetting parentheses around parameters

3. Consider this stored procedure call:
CALL CalculateDiscount(100, 0.1);
If the procedure returns the discounted price by subtracting the discount (price * rate), what is the expected output?

medium

A. 10

B. 110

C. 90

D. 100

Solution

1. Step 1: Understand inputs and calculation

   Price is 100, discount rate is 0.1 (10%). Discount amount = 100 * 0.1 = 10.

2. Step 2: Calculate discounted price

   Discounted price = 100 - 10 = 90.

3. Final Answer:

   90 -> Option C

4. Quick Check:

   100 - (100*0.1) = 90 [OK]

Hint: Subtract price * rate from price for discount [OK]

Common Mistakes:

• Adding instead of subtracting discount
• Using discount rate as final price
• Confusing discount amount with discounted price

4. You have this stored procedure call:
CALL UpdateUserEmail(123, '[e-mail]');
But it returns an error: ERROR: procedure UpdateUserEmail does not exist.
What is the most likely cause?

medium

A. The procedure name is misspelled or does not exist

B. The email format is invalid

C. The user ID 123 does not exist

D. The database connection is lost

Solution

1. Step 1: Analyze error message

   The error says the procedure does not exist, which means the database cannot find a procedure named UpdateUserEmail.

2. Step 2: Identify likely cause

   This usually happens if the procedure name is wrong or it was not created.

3. Final Answer:

   The procedure name is misspelled or does not exist -> Option A

4. Quick Check:

   Error about procedure existence = name or creation issue [OK]

Hint: Check procedure name spelling and existence first [OK]

Common Mistakes:

• Assuming input data causes procedure not found error
• Blaming connection issues without checking procedure
• Ignoring error message details

5. You want to test a stored procedure CalculateTax that takes an income amount and returns tax owed.
The procedure has a bug: it returns NULL for zero income instead of 0.
Which test case will best detect this bug?

hard

A. Call CalculateTax(1000) and check if result is positive

B. Call CalculateTax(0) and check if result is 0

C. Call CalculateTax(-100) and check for error

D. Call CalculateTax(NULL) and check for NULL

Solution

1. Step 1: Understand the bug

   The procedure returns NULL instead of 0 when income is zero.

2. Step 2: Choose test case to detect bug

   Testing with zero income and expecting 0 will reveal if NULL is returned incorrectly.

3. Final Answer:

   Call CalculateTax(0) and check if result is 0 -> Option B

4. Quick Check:

   Test zero input to catch NULL instead of 0 bug [OK]

Hint: Test edge inputs like zero to find null bugs [OK]

Common Mistakes:

• Testing only positive values misses zero case
• Testing negative income when not required
• Assuming NULL input tests zero income bug