Post #2557

✅Data Analyst Interview Questions with Answers: Part-2 11. What is structured data? Structured data is organized in rows and columns with a fixed schema, making it easy to store and query using SQL. Example: Sales tables, customer databases. 12. What is semi-structured data? Semi-structured data does not follow a strict table format but contains tags or keys. Example: JSON files, XML data, API responses. 13. What is unstructured data? Unstructured data has no predefined format. Example: Emails, images, videos, customer reviews text. 14. What is a database? A database is an organized system used to store, manage, and retrieve data efficiently. Example: MySQL, PostgreSQL, SQL Server. 15. Difference between OLTP and OLAP? OLTP (Online Transaction Processing) → Handles daily transactions (e.g., orders, payments). OLAP (Online Analytical Processing) → Used for reporting and analysis. 16. What is a primary key? A primary key uniquely identifies each record in a table. Example: Customer_ID in a customer table. 17. What is a foreign key? A foreign key links one table to another using the primary key of another table. Example: Customer_ID in Orders table linking to Customers table. 18. What is a fact table? Fact table contains measurable business data like sales, revenue, or quantity. 19. What is a dimension table? Dimension table contains descriptive details like customer name, region, product category. 20. What is a data warehouse? A data warehouse is a centralized system that stores large volumes of historical data for analysis and reporting. Double Tap ♥️ For Part-3