data modeller Interview Questions and Answers

Data modeling is the process of creating a visual representation of data structures and relationships within a business domain.

• Data modeling helps in organizing and understanding complex data systems.

• It involves identifying entities, attributes, and relationships between data elements.

• Examples include entity-relationship diagrams, UML diagrams, and data flow diagrams.

OLTP is for transaction processing, OLAP is for analytics and reporting.

• OLTP stands for Online Transaction Processing, used for real-time transaction processing.

• OLAP stands for Online Analytical Processing, used for complex queries and data analysis.

• OLTP databases are normalized, while OLAP databases are denormalized for faster query performance.

• OLTP systems are optimized for write operations, while OLAP systems are optimized for read operations.

• Example: OLTP system - online ...read more