60+ Business Technology Analyst Interview Questions and Answers

The task is to determine the total number of ways to make change for a specified value using given denominations of coins.

• Create a function that takes the number of denominations, the denominations array, and the value to make change for as input parameters.

• Use dynamic programming to iterate through all possible combinations of coins to make the change.

• Keep track of the number of ways to make change for each value from 0 to the target value.

• Return the total number of ways to ...read more

Sort an integer array containing only 0s, 1s, and 2s in-place using a single scan.

• Iterate through the array using three pointers to keep track of 0s, 1s, and 2s.

• Swap elements based on the current element value and the pointers.

• Example: If current element is 0, swap it with the element at the 0s pointer and increment both pointers.

To burst all balloons by shooting arrows from left to right, determine the minimum number of arrows needed.

• Iterate through the array and keep track of the maximum height of balloons that can be burst with one arrow.

• Increment the arrow count whenever a balloon height exceeds the maximum height.

• Return the total arrow count needed to burst all balloons.

Implement a function to count the number of occurrences of a given string within another string in linear time.

• Use the Z algorithm to preprocess the pattern string and the concatenated string to efficiently count occurrences.

• Iterate through the Z array to find matches of the pattern within the concatenated string.

• Return the count of matches found.

• Example: For S = 'ababa' and P = 'ab', the output should be 2.

Use SQL query to generate a report of customer churn based on case study data.

• Identify the criteria for customer churn in the case study data (e.g. last purchase date, account status)

• Select the relevant fields from the database tables (e.g. customer ID, churn date)

• Filter the data to include only customers who meet the churn criteria

• Group the data by relevant time periods (e.g. monthly, quarterly) to analyze churn trends

• Calculate the churn rate by dividing the number of churne...read more

Convert a given min-heap array into a max-heap array.

• Iterate through the given min-heap array and build a max-heap array by swapping elements.

• Start from the last non-leaf node and heapify down to maintain the max-heap property.

• Ensure that the output array satisfies the max-heap property.

• Example: For min-heap [1,2,3,6,7,8], the max-heap would be [8,7,3,6,2,1].

To convert a Minheap to a Maxheap, we can use a bottom-up approach to adjust the heap properties.

• 1. Start from the last non-leaf node and move upwards.

• 2. For each node, apply the heapify process to ensure the Maxheap property.

• 3. Swap the node with its largest child if it violates the Maxheap property.

• 4. Repeat the process until the root node is reached.

• 5. Example: For array [1, 3, 5, 7, 9], after conversion, it becomes [9, 7, 5, 3, 1].

To maintain knowledge transfer of project/jobs developed, ensure documentation, training, and continuous communication.

• Document all project/job details, processes, and procedures.

• Provide training sessions to transfer knowledge and skills.

• Encourage continuous communication and collaboration among team members.

• Establish a knowledge sharing platform or repository.

• Conduct regular knowledge transfer meetings or workshops.

• Assign mentors or experienced team members to guide and supp...read more

A dangling pointer is a pointer that points to a memory location that has been deallocated or freed. Dereferencing it can cause a program to crash.

• Dangling pointers occur when memory is freed or deallocated, but the pointer still points to that memory location.

• Dereferencing a dangling pointer can cause a segmentation fault or access violation.

• Dangling pointers can be avoided by setting the pointer to NULL after freeing the memory it points to.

SQL can be utilized in various business scenarios to analyze data and derive insights for decision-making.

• Data Analysis: Use SQL to query sales data to identify trends over time, e.g., SELECT AVG(sales) FROM sales_data WHERE date BETWEEN '2023-01-01' AND '2023-12-31'.

• Customer Segmentation: SQL can help segment customers based on purchase behavior, e.g., SELECT customer_id, COUNT(order_id) FROM orders GROUP BY customer_id HAVING COUNT(order_id) > 5.

• Performance Metrics: Calcula...read more

The date 02/02/2020 is a palindrome.

• A palindrome is a word, phrase, number, or other sequence of characters that reads the same forward and backward.

• 02/02/2020 reads the same forward and backward.

• Other palindromic dates in 2020 include 11/02/2020 and 22/02/2020.

If a microservice goes down in microservices architecture, it can affect the entire system.

• Other microservices may not be able to communicate with the downed microservice.

• The system may experience latency or errors.

• Proper monitoring and redundancy can help mitigate the impact of a downed microservice.

Types of polymorphism in OOP include compile-time polymorphism (method overloading) and runtime polymorphism (method overriding).

• Compile-time polymorphism: achieved through method overloading, where multiple methods have the same name but different parameters.

• Runtime polymorphism: achieved through method overriding, where a subclass provides a specific implementation of a method defined in its superclass.

• Example: Compile-time polymorphism - having multiple calculateArea metho...read more

To use a particular type of shell like korn or bash shell in shell scripting, specify the shell at the beginning of the script.

• Specify the shell at the beginning of the script using the shebang line (#!/bin/bash for bash shell, #!/bin/ksh for korn shell, etc.)

• Make sure the specified shell is installed on the system where the script will be executed

• Use shell-specific syntax and features in the script based on the chosen shell

An index in SQL is a data structure that improves the speed of data retrieval operations on a database table.

• Indexes are used to quickly locate data without having to search every row in a table.

• They can be created on one or more columns in a table.

• Examples of indexes include primary keys, unique keys, and non-unique indexes.

Fact and dimensions are components of a data warehouse. Facts are numerical data while dimensions are descriptive data.

• Facts are quantitative data that can be measured, such as sales revenue or number of customers.

• Dimensions are descriptive data that provide context for the facts, such as time, location, or product.

• Facts and dimensions are stored in a data warehouse, which is a large repository of data used for analysis and reporting.

• Facts are stored in fact tables, while dim...read more

Informatica Transformations are used to manipulate data during ETL process.

• Aggregator: performs calculations on groups of data

• Filter: filters rows based on a condition

• Joiner: joins data from two sources based on a common key

• Lookup: retrieves data from a database table or flat file

• Rank: assigns a rank to each row based on a specified column

• Router: routes data to different targets based on a condition

• Sorter: sorts data based on one or more columns

• Source Qualifier: extracts data...read more

Function overloading is having multiple functions with the same name but different parameters. Function overriding is having a derived class implement a method with the same name and parameters as a method in the base class.

• Function overloading is a compile-time polymorphism concept.

• Function overriding is a run-time polymorphism concept.

• Function overloading is used to provide different ways of calling the same function.

• Function overriding is used to provide a specific impleme...read more

How to make a class immutable in Java?

• Make all fields private and final

• Do not provide any setter methods

• Make the class final

• If mutable fields are present, return a copy of them in getter methods

Block level corruption can be found using tools like checksums and resolved by restoring from backups or repairing the corrupted blocks.

• Use checksums to detect block level corruption by comparing the checksum of the data against a known good checksum.

• Regularly run integrity checks on storage devices to identify any corrupted blocks.

• Restore the corrupted blocks from backups if available, or repair them using tools like fsck.

• Isolate the corrupted blocks to prevent further data ...read more

SCD stands for Slowly Changing Dimensions. It is a technique used in data warehousing to track changes in data over time.

• Type 1 SCD: Overwrite the old data with new data. Example: Customer address change.

• Type 2 SCD: Create a new record for the change. Example: Employee promotion.

• Type 3 SCD: Create a new attribute to store the change. Example: Product price change.

• Type 4 SCD: Create a separate table to store the change history. Example: Customer purchase history.

A dangling pointer in C is a pointer that points to a memory location that has been deallocated, leading to potential crashes or undefined behavior.

• Dangling pointers occur when memory is deallocated but the pointer is not updated or set to NULL.

• Accessing a dangling pointer can result in reading or writing to invalid memory locations.

• Example: int *ptr = malloc(sizeof(int)); free(ptr); *ptr = 10; // Accessing a dangling pointer.

Design a database for a startup to increase revenue.

• Identify key business processes and data requirements

• Design a relational database schema to store the necessary data

• Optimize the database structure for efficient querying and data retrieval

• Implement data validation and integrity constraints

• Consider scalability and future growth

• Leverage data analytics and business intelligence tools for revenue optimization

Dynamic lookup is done at runtime while status lookup is done at design time.

• Dynamic lookup is used when the lookup values are not known at design time.

• Status lookup is used when the lookup values are known at design time.

• Dynamic lookup requires more processing power as it is done at runtime.

• Status lookup is faster as it is done at design time.

• Example of dynamic lookup: retrieving a list of available payment methods from a database.

• Example of status lookup: selecting a status...read more

The given HTML command is used to create a hyperlink in a webpage.

• The <a> tag is used to define a hyperlink in HTML.

• The href attribute specifies the URL of the page the link goes to.

• Text between the opening and closing <a> tags is the clickable text of the link.

To swap two numbers without using an extra variable, you can use arithmetic operations like addition and subtraction.

• Store the sum of the two numbers in one of the variables, then subtract one number from the sum to get the other number.

• For example, to swap numbers a=5 and b=10: a = a + b; b = a - b; a = a - b; Now a=10 and b=5.

I manage pressure by prioritizing tasks, practicing time management, seeking support from colleagues, and maintaining a healthy work-life balance.

• I prioritize tasks to ensure that I focus on the most important and urgent ones first.

• I practice time management techniques such as creating to-do lists and setting deadlines to stay organized and meet deadlines.

• I seek support from colleagues or mentors when feeling overwhelmed, as they can provide guidance or assistance.

• I maintain ...read more