What are some SQL queries you might be asked in an interview?

Question

Accepted Answer

SQL queries are essential for data extraction, transformation, and loading in ETL processes.

SQL stands for Structured Query Language, used for managing and manipulating databases.
Common SQL operations include SELECT, INSERT, UPDATE, and DELETE.
Example of a SELECT query: SELECT * FROM employees WHERE department = 'Sales';
JOIN operations are crucial for combining data from multiple tables, e.g., SELECT * FROM orders JOIN customers ON orders.customer_id = customers.id;
Aggregate functions like COUNT, SUM, AVG help in summarizing data, e.g., SELECT COUNT(*) FROM sales WHERE amount > 100;

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