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

Modifyand removing a sequence-sequences, Modify a sequence: ALTER SEQU...

Modify a sequence: ALTER SEQUENCE SEQSS INCREMENT 2 MAXVALUE 3000;   Removing a sequence: DROP SEQUENCE SEQSS;

Draw entity-relationship diagram of database, Read the description below a...

Read the description below and draw an Entity-Relationship diagram for it. You must use the symbols described in the course materials. This database will help the Parents Assocc

Find out the names and company names from database, Find out the names and ...

Find out the names and company names of all employees sorted in ascending order of company name and descending order of employee names of by which company. SELECT EMPLOYEE_NAME,

Speedup query processing, Speedup Query Processing: A query that includes d...

Speedup Query Processing: A query that includes data at various sites can be split into sub-queries. These sub- queries can be implemented in parallel by various sites. Such parall

Determine the concept of process, Determine the concept of Process Pro...

Determine the concept of Process Process: A process transforms the data values. It is represented as ellipse containing a description of transformation. Each procedure has a

What are costs to be considere when transaction is roll back, What are the ...

What are the costs to be considered when a transaction has to be rolled back when recovering from deadlock?         Ans: A few transaction will must rolled back (made a victim)

Components of a typical database environment, Question: (a) List four d...

Question: (a) List four disadvantages of the File Processing System as compared to the Database Systems. (b) The integrity of a database is enforced by integrity rules. One

Define the query optimisation, Define the Query optimisation The query ...

Define the Query optimisation The query parser commonly generates a standard initial tree to correspond to an SQL query, with no doing any optimization. Such type of a canonica

Explain the advantages of database management system, Advantages of Databas...

Advantages of Database management system Let us summarize the advantages. Reduction of Redundancy: This is perhaps the most important advantage of using DBMS. Redundancy i

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