Helm360 Interview Questions, Process, and Tips

SQL is a programming language used to manage and manipulate relational databases.

• SQL stands for Structured Query Language

• It is used to create, modify, and query databases

• Common SQL commands include SELECT, INSERT, UPDATE, and DELETE

• SQL is used in various industries including finance, healthcare, and e-commerce

Joins are used in SQL to combine data from two or more tables based on a related column.

• INNER JOIN returns only the matching rows from both tables

• LEFT JOIN returns all rows from the left table and matching rows from the right table

• RIGHT JOIN returns all rows from the right table and matching rows from the left table

• FULL OUTER JOIN returns all rows from both tables

• CROSS JOIN returns the Cartesian product of both tables

Developed a predictive model to forecast sales for a retail company

• Used historical sales data to train the model

• Incorporated external factors such as weather and holidays

• Evaluated model performance using metrics like RMSE and MAE