Relational DB, Database Management System

Assignment Help:
Suppose R is a relation with attributes A1, A2,..., An. As a function of n, tell how many superkeys R has, if:
1.1 The only key is A1.
1.2 The only key is A1 and A2.
1.3 The only key is {A1 A2} and {A3 , A4}.
1.4 The only key is {A1 A2} and {A1 , A3}.

Related Discussions:- Relational DB

Optimistic concurrency control, Optimistic Concurrency Control Is locki...

Optimistic Concurrency Control Is locking the only way to stop concurrency related problems? There exist some other ways too. One such way is known as an Optimistic Concurrency

Project operation, The PROJECT operation The project operation is used t...

The PROJECT operation The project operation is used to choose the records with specified attributes as discarding the others based on some related criteria. This is denotes as ∏

What do you mean by atomicity and aggregation, What do you mean by atomicit...

What do you mean by atomicity and aggregation? Atomicity : Either all actions are carried out or none are. Users should not have to worry about the effect of incomplete trans

Difference among a database schema and a database state, What is the differ...

What is the difference among a database schema and a database state? The collection of information stored in database at particular moment in time is known as database state a

Need some database of usa and uk, I want Database Of United Kingdom with Cr...

I want Database Of United Kingdom with Criteria of:\r\n\r\n1). Name, Number, City, State, Postal Code, Address, Email id, DOB.\r\n\r\n2). Unsecure Debts only adds Credit Card Payme

Explain what is aggregation, Explain what is Aggregation? Aggregation:...

Explain what is Aggregation? Aggregation: Aggregation is an significant concept in database design whereas composite objects could be modelled during the design of database a

What is the use of group by clause, What is the use of group by clause? ...

What is the use of group by clause? Group by clause is used to be relevant aggregate functions to a set of tuples. The attributes given in the group by clause are used to shape

What are the two main goals of parallelism, What are the two main goals of ...

What are the two main goals of parallelism? Load -balance multiple small accesses, so that the  throughput of such accesses enhances. Parallelize large accesses so that the res

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd