{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

20 pts dbase a pet salon has the following very

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: the process control block iv. Pre ­emptive scheduling technique similar to round ­robin d. (3 pts) If the following jobs are scheduled in the order shown in round ­robin fashion, what is the average completion time? Parenthesized numbers show the time required for each job in milliseconds. Assume each time slice is 10 ms. Job 1 (10); Job 2 (20); Job 3 (30); Job 4 (40). 12. 10 pts [File sys/directories] Give one ­sentence answers for a. through d. a. What is the difference between a relative and an absolute path? b. What is the “Scan” method for disk scheduling? c. What is a ”file extension” and why is it important? d. What is meant by the “root directory”? e. The structure of a file system is naturally modeled as (circle one) i. paged memory ii. a database iii. a graph iv. a tree v. an array 6 13. 20 pts [Dbase] A pet salon has the following very simple database to keep track of the pets and their owners. Customers TABLE Pets TABLE cust_id 1 John 2 name Mary owner_id petname 1 Fido 2 Fluffy 2 Bowser For parts a. through e., draw the table which is the result of the query: a. 3pts SELECT petname FROM Pets WHERE owner_id = 2 b. 3pts SELECT * FROM Pets WHERE petname LIKE “%o%” c. 3pts SELECT petname FROM Pets WHERE petname LIKE “B_” d. 3pts SELECT name, petname FROM Customers, Pets WHERE cust_id = owner_id 7 e. 3pts SELECT * FROM Customers, Pets f. 1 pt True or False? An advantage of using multiple tables in a database is to allow for the replication of data so that data won’t be lost. g. 4 pts Write a query that returns the names of the owners who have pets whose names begin with “F”. (The query should work regardless of what additional recor...
View Full Document

{[ snackBarMessage ]}