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!
During the deletion of a tuple two cases can happen:
Deletion of tuple in relation having the foreign key: In this type of case simply delete the desired tuple. For example, in ASSIGNMENT relation we can simply delete the first tuple.
Deletion of the target of a foreign key reference: For instance, an attempt to delete an employee tuple in EMPLOYEE relation whose EMPID is 101. This employee shown not only in the EMPLOYEE but also in the ASSIGNMENT relation. Can these tuple be deleted? If we delete the tuple in EMPLOYEE relation then two unequalled tuples are left in the ASSIGNMENT relation, therefore causing violation of referential integrity constraint. Therefore, the following two choices be for such deletion:
RESTRICT - The delete operation is "restricted" to only the situation where there are no such matching tuples. For instance, we can delete the EMPLOYEE record of EMPID 103 as there is no matching tuple in ASSIGNMENT but not the record of EMPID 101.
CASCADE - The delete operation "cascades" to delete also those matching tuple. For instance, if the delete mode is CASCADE then deleting employee having
EMPID as 101 from EMPLOYEE relation will also make deletion of 2 more tuples from ASSIGNMENT relation.
Need a sample of a clinic database relationships
Explain ODBC? ODBC - Open DataBase Connectivity (ODBC) enable the integration of SQL along with a general-reasons programming language.
Explain four causes for failures in data warehouse projects
Many-to-many : Entities in A and B are related with any number of entities from each other. Example: Taught_by Relationship among course and faculty. One faculty member ca
Q. State the Technique for converting a state diagram to code. i) Identify the major control path. Starting with first state, find the path from diagram that corresponds
What is a records management consultation? Our organization is an authority for disseminating your specific requirements and giving you with a solution to effectively manage yo
The need for three level architecture The aim of the three level architecture is to divide each user's view of the database from the way the database is physically shown.
Which method is used to key transformation ? A hash method is used to key transformation.
Give the general form of SQL query? Select A1, A2............., An From R1, R2..............., Rm Where P
Question: a) What is Client/Server and what benefits can be expected from Client/Server systems? b) Explain what middleware is and what it does. Why would MIS managers be p
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