Derived Tables

1. Derived Tables are nothing but using a result of a query as a table.
2. This is much better than using temporary tables.
3. This increases the performance.
4. The below shows how to return employee and department info for those who don’t belong to a inactive department

Select EmployeeID, FirstName, LastName, Dt.DeptName from Employee INNER JOIN (Select * from Dept where Status !='InActive') Dt ON Dt.DeptID = Employee.DeptID

Comments

M S Banu Prakash Raje Urs said…
Whats the diff between using regular inner and derived table for this particular example?
7:28 PM
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