Writing "correct" code is only the first step; high-level T-SQL skill involves writing efficient and clean code . How to write efficient TSQL - SQLServerCentral
Tools like CASE expressions allow developers to apply "if-else" logic directly within a query without moving data back to an external application. Best Practices for Performance and Readability T-SQL Querying
These provide a way to encapsulate logic, making complex queries more readable and maintainable . Writing "correct" code is only the first step;