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!
Update or Modify operation alters the existing values. If these operations alter the value that is the foreign key also, the only check need is the similar as that of the Insert operation.
What should happen to an try to update a candidate key that is the objective of a foreign key reference? For instance, an attempt to update the PROJID "LG" for which there exists at least one matching ASSIGNMENT tuple? In common there are the similar possibilities as for DELETE operation:
RESTRICT: The update operation is "restricted" to the case where there are not matching assignment tuples. (it is rejected otherwise).
CASCADE - The update operation "cascades" to update the foreign key in those matching assignment tuples also.
(a) Provide the description of the following ODMG schema in the Object Definition Language (ODL). (b) Based on the above object database, write the following queries i
What is transaction? Transaction is a unit of program implementation that accesses and possibly updated several data items.
What is meant by Physical blocks? The input and output operations are completed in block units. The blocks residing on the disk are referred to as physical blocks.
what is physical data structure
What is the use of sub queries? A sub query is a select-from-where expression that is nested with in another query. A common use of sub queries is to do tests for set membershi
Explain mechanism of nested queries? SQL gives a mechanism for nesting subqueries. A subquery is a select from where expression that is nested within one more query. A common u
Objectives After Reading this part, you should be able to: Explain the term CONCURRENCY; Describe the term transaction and concurrent transactions; Talk about co
An entity set that does not have sufficient attributes to form a primary key is called? An entity set that doesn't have sufficient attribute to form a primary key is known as w
Sub query in the UPDATE command : Example : //Double the commission for employees, who have got at least 2 increments. UPDATE EMP SET COMM = COMM * 2 WHERE
Distributed Control and Data sharing: The geographical distribution of an organization can be showed in the distribution of the data; if a number of different sites are linked to e
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