Complex SQL Queries: Combining Joins, Group By & Subquery as Derived Table | T-SQL Course Part 20 скачать в хорошем качестве

Complex SQL Queries: Combining Joins, Group By & Subquery as Derived Table | T-SQL Course Part 20

It’s time to bring it all together! In this advanced practical lesson, we combine everything we’ve learned—Joins, Group By, and Subqueries—to solve complex real-world reporting tasks. The Main Challenge: How to retrieve full employee details for the person earning the highest salary in each specific department. In this video i will use subquery in the form of a table which is also called Derived Table. To this Derived Table i will give an alias name to the query, then that alias i can treat it like a table. What you will learn in this session: Multi-Step Problem Solving: Breaking down a complex request into a "Derived Table." Advanced Joins: Joining a physical table with a virtual "Subquery" result. Aggregating by Category: Finding the Max Salary per Department using Group By. Data Integrity: Ensuring you return the correct Name and City for the specific salary found. Derived Tables: Understanding how to treat a query result as a temporary table (DT). I covered following queries in the video SIMPLE SUBQUERY: Return the single highest earner in the company JOIN + SUBQUERY: Return highest earner with their Department Name THE MASTER QUERY: Highest Salary PER Department , We use a Derived Table (DT) to find the max salary for each ID, then join it back to the main table to get the employee's name. #SQLServer #TSQL #ComplexQueries #DerivedTable #SQLJoins #DataAnalysis #SQLInterviewQuestions #LearnSQL #databasedevelopment