提取表和子查詢的區別(derived table vs subqueries)

子查詢，你們再熟悉不過了，例如：spa select employee_name from employee where employee_salary >翻譯 (select avg(employee_salary) from employee)table 下面這也是一個子查詢，沒用到where語句。sed INSERT INTO math_study_group(id, name) SELEC

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