Database fundamentals and SQL

Understanding : Discussion of Employees, Departments, Jobs, and their relationships( HR Schema). Data Fields: Review of fields such as Employee ID, Name, Salary, and Hire Date. GROUP BY vs. DISTINCT: Explanation of their differences and performance. Aggregate Functions: Overview of COUNT, SUM, AVG, MIN, and MAX. Date Queries: Troubleshooting date formats and using MM/DD/YYYY. Discussion on functions like TO_DATE and TO_CHAR.