Qapitol Qa Interview Questions and Answers

This code counts the occurrences of each character in a given string using a HashMap in Java.

• Use a HashMap<Character, Integer> to store characters and their counts.

• Iterate through each character of the string using a for loop.

• For each character, update its count in the HashMap.

• Example: For the string 'hello', the output will be: {h=1, e=1, l=2, o=1}.

This Java code increments the last element of an array, handling overflow by resetting to zero if it exceeds 9.

• Increment Last Element: The last element of the array is incremented by 1.

• Overflow Handling: If the incremented value exceeds 9, it resets to 0 and increments the second last element.

• Example 1: For input [1,2,3,4], output is [1,2,3,5].

• Example 2: For input [1,2,3,9], output is [1,2,4,0].

• Edge Case: For inpu...read more

Regression testing is the process of retesting a software application to ensure that new code changes have not adversely affected existing functionality.

• Performed after code changes to ensure no new bugs have been introduced

• Helps maintain the quality and stability of the software

• Automated tools can be used to streamline the process

• Examples: running test cases after a software update, checking for bugs after adding...read more

Functional testing is a type of software testing where the system is tested against the functional requirements/specifications.

• Tests the functionality of the software

• Focuses on what the system does

• Verifies that the system behaves as expected

• Does not concern with how the system works internally

• Examples: testing login functionality, search feature, data validation

SQL queries are essential for data retrieval and manipulation in real-life applications, especially in testing scenarios.

• Use JOINs to combine data from multiple tables, e.g., SELECT * FROM Orders JOIN Customers ON Orders.CustomerID = Customers.CustomerID.

• Implement WHERE clauses to filter results, e.g., SELECT * FROM Products WHERE Price > 100.

• Utilize GROUP BY for aggregating data, e.g., SELECT COUNT(*), Categor...read more

Integration testing is a type of testing where multiple components are tested together to ensure they work as expected.

• Test cases should cover all possible combinations of inputs and outputs

• Test cases should include both positive and negative scenarios

• For an ATM, test cases should cover withdrawal, deposit, balance inquiry, and error scenarios

• Test cases should also cover integration with external systems such as t...read more