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!
It defines that the tuple in one relation that refers to another relation must refer to an existing tuple in that relation. This constraint is states on two relations (not essentially distinct). It uses a concept of foreign key and has been dealt with in more factors in the next unit.
Example
In the example given above, the value of C^ in every R tuple is matching with the value of C# in some S tuple. If a tuple has values (A6, B2, and C4) is added then it is invalid as referenced relation S doesn't contain C4. Therefore, it will be a violation of referential integrity constraint.
Properties of a Transaction A transaction has four main properties. These are: Atomicity Consistency Isolation or Independence Durability or Permanen
In which form of relational database developer refers to a record? In a tuple form of relational database developer refers to a record.
Explain Candidate key? Candidate Key - A candidate key is a minimal superkey, that can be used to uniquely identify a tuple in the relation.
State the Steps of Object Design Object design is a very iterative process in which various classes, relationships among objects are added when you move from one level to
I want an iPad app that is a simple 1 page form to complete with text. The Objective is to allow a few dozen people of the same organization (they're all on iPad) to open the app,
An instance of relational schema R (A, B, C) has distinct values of A including NULL values. then A is a candidate key or not? If relational schema R (A, B, C) has distinct val
Two Phase Locking (2PL) The two-phase locking protocol having of two phases: Phase 1 : The lock acquisition phase : If a transaction T needs to read an object, it wants to
Define check point and its impact on data base recovery. Ans: There could be hundreds of transactions handled per minute, in a large on-line database system.
What are the causes of bucket overflow in a hash file organization? What can be done to reduce the occurrence of bucket overflow? When a record is inserted, the bucket to that
Advantages of Data Distribution The primary benefit of distributed database systems is the ability to access and share data in a reliable and efficient manner.
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