Optimize the following SQL Query by using Query Tree and Heuristic Rules: SELECT C.Fname, E.Fname FROM Employee AS E, Customer AS C, Order AS O WHERE E.EMP_ID=O.E_ID AND C.City=’Jeddah’ AND C.Customer_ID=O.C_ID AND E.EMP_ID=’12943’   You should show the Initial Query Tree and add a screenshot of the Query Tree after applying each rule

You will produce a query result set of Products that have a P_PRICE (Price) that is greater than the Average of all the Product's Prices. For instance if there were three products that had a price of (400.00, 300.00, 500.00) then the average would be $400.00. Therefore if you printed it out, there would only be ONE that satisfied the condition of being Greater than the average.  In the screen shot below the Average was actually 56.42.  Please look at screen output so you can detect how it is sorted by, and which columns you should use. Please use the PRODUCT Table from aboveYour task is to write the SQL to generate the result set below. Hint: You likely will have to use a subquery

You have two tables teachers and students. Each student belongs to a teacher. Complete the query to join the tables on the teacher id. SELECT * FROM students   JOIN teachers   ON _________ ; a. Students.teacher_id = teachers.id b. teachers_id = id c. teachers.id = student.id d. teachers = students.id

The query optimizer constructs an initial query tree using join, selection, and projection operations. (a) True (b) False