In MySQL it's about 4 seconds vs. about 1.5 minutes. I believe MySQL is creating a temporary table with the entire contents of the subquery where as SQL Server's optimizer is doing something smarter.

Subqueries are a powerful tool that you can use in all four SQL data statements. In this chapter, I’ll show you how subqueries can be used to filter data, generate values, and construct temporary data ...

create a table called “emp_manager” (emp_no – integer of 11, not null; dept_no – CHAR of 4, null; manager_no – integer of 11, not null). /*Fill emp_manager with data about employees, the number of the ...