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!
What is completeness constraint on generalization? Define the variation between total and partial design constraint. Give an example each.
Ans: Completeness Constraints
1. Total specialization constraint
a. Each entity in the superclass should be a member of some subclass in the specialization for example {HOURLY_EMPLOYEE, SALARIED_EMPLOYEE}
b. Notation: superclass
2. Partial specialization constraint an entity might not belong to any type of the subclasses
For example: {SECRETARY, ENGINEER, TECHNICIAN}
Write short notes on relational constraints? Relational Constraints are: 1. NOT NULL 2. Unique 3. Primary key 4. Foreign key 5. Table check
Define Two phase commit Two phase commit: To make sure atomicity, all the sites where a transaction is being executed must agree on the final outcome of the execution. The tran
What are the benefits of prepared statements and place holders? Parameter binding operations automatically handle escaping of characters Encourage Statement reuse
construct an er diagram for a hospital with a set of patients and a set of medical doctors. associate with each patient a log of various test and examination conducted.convert er d
Derived horizontal fragmentation: Some applications may include a join of two or more relations. If the relations are stored at dissimilar locations, there may be a major overhead
Example: //REVOKE ALL ON EMP FROM MCA12; (All permissions will be cancelled) You can also cancel only some of the permissions. Drop: A user-
What is banker's algorithm? Banker's algorithm is a deadlock avoidance algorithm that is applicable to a resource-allocation system with multiple instances of each resource ty
As with other software, databases can potentially be used for unethical purposes. As a database developer, and a consumer, you should recognize database misuse, and how it may affe
Determine the Objectives of object oriented design provide an overview of object oriented design; partitioning system to subsystems; describe how a software desig
Deadlock And Its Prevention: As seen earlier, though two phase locking protocol handles the trouble of serialisability, but it causes some troubles also. For instance, consider th
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