Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
(a) Design a query plan for the following distributed query: An application at site B wants to compute a join of STUDENT ?Id=StudId TRANSCRIPT where STUDENT (Id,Major) is at site B and TRANSCRIPT (StudId, CrsCode) is at site C. The result should be returned to B. Assume that semijoin is not used. Also assume that
(b) Estimate the cost of computing σMajor='CS' (STUDENT) ?Id = StudId TRANSCRIPT using the semijoin strategy. Use the sizes of the STUDENT and TRANSCRIPT relations and of their attributes from the part (a) above. In addition, assume that 10% of the students major in CS. Compare this with the solutions in part (a) above that do not use the semijoin.
What are the typical phases of query processing
Example: RELATIONAL SCHEMA for PERSON: PERSON (PERSON_ID: integer, NAME: string, AGE: integer, ADDRESS: String) RELATION INSTANCE In this instance, m = 3 and n = 4
When is a transaction rolled back? Any changes that the aborted transaction made to the database must be uncompleted. While the changes caused by an aborted transaction have be
What is Normalization? Database normalization is a data design and organization method applied to data structures based on rules that help building relational databases. In rel
Advantages of Data Distribution The primary benefit of distributed database systems is the ability to access and share data in a reliable and efficient manner.
Related fields in a database are grouped in which form? Related data fields in a database are grouped to form a data record. (A record is a collection of related fields)
What exactly is the concept of Functional Dependencies? And how do we associate this concept with the logic of Super-keys, Candidate Keys, etc? Given Relation R(A,B,C,D,E) with de
Object-oriented decompositions Object-oriented decompositions of systems better are able to cope with change. Each subsystem has a well-defined interface which communicates with
Let us now make the E-R diagram for the student database as per the explanation given in the previous section. We can also states the overall logical structure of a database usi
what does glory be mean
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd