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!
Define entity integrity and referential integrity. How does SQL allow specification of these?
Ans: Entity Integrity Rule- If the attribute A of relation R is a prime attribute of R after that A cannot accept null values.
Referential Integrity Rule- In referential integrity, it is made sure that a value that appears in one relation for a given set of attributes as well appears for a particular set of attributes in another relation.
In SQL, referential integrity and entity integrity rules are implemented as constraints on the relation known as reference Key constraint and primary Key constraint correspondingly.
These constraints can be fixed with relation at the time of creation of the relations or after the creation of the relations by altering the definition of the relations. For instance:
What is a dataset? A dataset is an in-memory database that is disconnected from any regular database, but has all the significant characteristics of a regular database. Dataset
What is the archtetype/instance pattern? The archetype/instance pattern happens when one entity tracks occurrences of another entity. A common example is the relationship among
Can i get help with weka software
atient(PNumber, Name, NHS_no, Amount_due, DNO, Doctor, Medical_Treatment), relation of schema Staff(StaffNum, Name, DNO, Task) and relation of schema Dept(DNO, Name, Location, Dire
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
Creating views with Read only option : In the view definition this option is used to make sure that no DML operations can be done on the view.
Explain several types of constraints that can be specified using CREATE TABLE command. Explain CASCADE and RESTRICT clauses of DROP SCHEMA command? Constraint Description PRIM
sql is relationally complete-justify
State the Object Design for Processing The object design phase comes after analysis and system design phase. The object design phase includes implementation details like as i
What is self-transition? If there is a transition which goes back to same state, it is known as "self- transition." With a trigger action exit action would be executed f
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