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Explain the concept of ACID properties in DBMS in your own words?

Patient # =1111

Surgeon# = 311

Surgery Date = 12.Jun.95

Patient Name = John White

Patient Address = 15 New St., New York, NY

Surgeon Name = Michael Diamond

Surgery = Kidney stones removal

Drug admin = None

Side effects = Rash

1. What normal form is the relation in ?
2. If it is not in 3NF convert into 3NF.Explain your answer.

Description: 

Design and develop an application for daily student attendance in schools, 

universities, and institutes. If facilitates to access the attendance information of 

a particular student in a particular class. This system will also help in evaluating 

the attendance eligibility criteria of a student. The student attendance system 

helps teachers to mark the online attendance of students during class & reduce 

manual work. It is used to track student's attendance, absentee record, 

attendance history & other related documents.

2.3 Given the relations R (A, B) and S (B, C) where values are all integers. Examine the undermentioned three relational algebra expressions: a. A, C(R⋈B=1S) b. A(B = 1R)XC(B = 1S) c. A, C (ARXB = 1S) Two of the three expressions are equivalent (i.e., they produce the same answer on all databases), while one of them can produce a different answer.

2.3.1 Which query can produce a contrasting answer? Give the simplest database instance you can think of where a different answer is produced. (5)

2.3.2 Why do we care that the expressions are equivalent? (5)

2.3.3 How can we determine that the expressions are equivalent?

2.1 Assuming the following relations from a customer database, write relational algebra expression for each statement using symbolic notations. Customer (cid, cname, rating, salary) Item (iid, iname, type) Order (cid, iid, day, qty)

2.1.1 Find the names of customers who have ordered item with id 087. (2)

2.1.2 Find the names of customers who have ordered a television i.e., an item of type television. 

2.2 Consider the following relations from a Richfield database. Write relational algebra expression for each statement using symbolic notations. Books (bid, title, publisher, year) Students (sid, sname, major, age) Authors (aid, aname, aaddress) Borrows (bid, sid, date) 2.2.1 List the title & year of each book.

2.2.2 Find all information about students whose major is Java.

2.2.3 List all students with the books they can borrow.

2.2.4 Obtain all the books published by McGraw-Hill before 2019.

2.2.5 Rename aname in the relation Authors to name. 

2.2 Use information on MYSQL student_reg table to login making sure you are using proper credentials.

2.3 Register button should take the user to a new page that allows them to register if they are not registered in the system.

2.4 If student’s credentials do not match the one in the database when trying to login, the page should display login error message and only three attempts are permitted before the user is kicked out of the system for 30 minutes

Polly Pipe is a water sports provider and installer based in Braintree, England. They need you to design and implement a database that meets the data requirements. These necessities are defined in this scenario and below are samples of the paper records that the Polly Pipe preserves.

Polly Pipe is focused in placing aquariums at business customers. Customers can request several installations, but each installation is tailor-made for a specific customer. Facilities are classified by type. One or more employees are assigned to each facility. Because these facilities are often very large, they can include carpenters and masons as well as water installers. The facilities use equipment such as aquariums, air pumps and thermostats. There can be multiple computers in a facility.

Below are examples of paper records that Polly Pipe currently maintains.

Create a Entity Relationship Diagram with cardinalities,primary keys,foreign keys,entities and attributes.

Polly Pipe is a water sports provider and installer based in Braintree, England. They need you to design and implement a database that meets the data requirements. These necessities are defined in this scenario and below are samples of the paper records that the Polly Pipe preserves.

Customers can request several installations, but each installation is tailor-made for a specific customer.The facilities use equipment such as aquariums, air pumps and thermostats.

1.1.Identify the user and system requirements to design a database for the above scenario and design a relational database system using conceptual design (ER Model) by including identifiers (primary Key) of entities and cardinalities, participations of relationships. Convert the ER Model into logical database design using relational database model including primary keys foreign keys and referential Integrities.