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:
how does Btree differ from a B+ - tree?
external view of DBMS in healthcare department?
Which operation is used if we are interested in only certain columns of a table? PROJECTION operation is used if we are interested in only certain columns of a table.
The following variant of the primary copy asynchronous-update replication protocol has been proposed for totally replicated systems. (a) A transaction executing at site A updat
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
In E-R Diagram how derived attribute are represented ? In E-R Diagram By Dashed ellipse derived attribute are represented.
differences between a classified catalog and a dictionary catalog
What are the ways of obtaining the connection parameters? Hardwire the parameters into the program. Ask for the parameters interactively. Get the parameters
Explain Relational model and their use in DBMS? Relational Model - The relational model was first introduced through E.F. Codd of the IBM Research in the year of 1970. The mode
Describe the tools that are available for managing MySQL Server. Given below are the tools to manage MySQL server: mysqld - MySQL server daemon. This is used to begain t
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