We have a query to retrieve the students with age 22 and studying in a CS 608 class. We can get all the student details from STUDENT table, and class details from the CLASS table. We can write this query in two different ways. I. SELECT std.* FROM STUDENT std, CLASS cls WHERE std.CLASS_ID = cls.CLASS_ID AND std.AGE = 22 AND cls.CLASS_NAME = 'CS608' II. SELECT std.* FROM (SELECT FROM STUDENT WHERE AGE =22) std, (SELECT FROM CLASS WHERE CLASS_NAME = 'CS608') cls WHERE std.CLASS_ID = cls.CLASS_ID Which of the following is true? O Query 2 is more efficient because Query 1 traverses the entire table to perform the join while Query 2 has filters on each table significantly reducing the cost The cost of Query 1 is less than Query 2 Query 1 is more efficient because Query 2 has filters on each table thus increasing the cost Query 1 is more efficient since Query 2 has filters on each table thus will traverse through more tuples

We have a query to retrieve the students with age 22 and studying in a CS 608 class. We can get all the student details from STUDENT table, and class details from the CLASS table. We can write this query in two different ways. I. SELECT std.* FROM STUDENT std, CLASS cls WHERE std.CLASS_ID = cls.CLASS_ID AND std.AGE = 22 AND cls.CLASS_NAME = 'CS608' II. SELECT std.* FROM (SELECT FROM STUDENT WHERE AGE =22) std, (SELECT FROM CLASS WHERE CLASS_NAME = 'CS608') cls WHERE std.CLASS_ID = cls.CLASS_ID Which of the following is true? O Query 2 is more efficient because Query 1 traverses the entire table to perform the join while Query 2 has filters on each table significantly reducing the cost The cost of Query 1 is less than Query 2 Query 1 is more efficient because Query 2 has filters on each table thus increasing the cost Query 1 is more efficient since Query 2 has filters on each table thus will traverse through more tuples

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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