MySQL Developer Roadmap

Write SQL Queries

Write SQL queries to retrieve employee names, filter by department, and calculate average salaries.

Expected output: Correctly filtered and aggregated query results.

Hint: Use SELECT, WHERE, GROUP BY, and aggregate functions.

Design a Simple Database Schema

Design a normalized schema for a library system including books, authors, and borrowers.

Expected output: An ER diagram or table definitions with keys and relationships.

Hint: Identify entities, primary keys, and relationships.

INNER JOIN returns only the rows with matching values in both tables, while LEFT JOIN returns all rows from the left table and matched rows from the right table, filling with NULLs when there is no match.

Indexes allow MySQL to find rows faster by creating a data structure that enables quick lookups, reducing the need for full table scans.

ACID stands for Atomicity, Consistency, Isolation, and Durability, which are key properties ensuring reliable transaction processing.