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!
Explain Domain calculus
Domain calculus is one of the types of the relational calculus. The formal specification of the domain calculus was planned after the development of the QBE system. Domain calculus has the variables range in excess of single value from domains of attributes. To create a relation degree n for a query result, we should have n domain variables - one for each attribute. An expression of the domain calculus is of the form {X | F(X)}
In which F is a formula on X and X denotes a set of domain variables. The expression characterizes X like F(X) is true.
A View may be defined of as a virtual table, that is, a table that does not really exist in its own right but is instead inferred from one or more underlying base data table. T
Define According to the levels of abstraction, the schema at the intermediate level is called Ans: As per to the levels of abstraction, the schema at the intermediate level is
Multilevel Indexing Scheme Consider the indexing scheme where the address of the block is consider in the index for each record, for a little file, this index would be little a
Explain Instance and schemas? Instances and schemas: Databases changes over time as the information is deleted and inserted. The collection of information stored in database
What is foreign key? Foreign Key - Let there are two relations in tables R and S. Any candidate key of the relation R that is referred in the relation S is known as the forei
In an organisation various projects are undertaken. Each projects can employ one or more employees. Every employee can work on one or more projects. Each project is undertaken on
How to create values of structured type? Constructor functions are used to make values of structured types. A function with the similar name as a structured type is a construct
Attributes attached to an entity can be of various types. Simple The attribute that cannot be further separated into smaller parts and shows the basic meaning is known as a
Define various ways in which SELECT statement can be used for record selection Technology? SELECT gives you control over a number of aspects for record retrieval: 1) Which
Determine the Persistent object Persistent object can be stored in one of the following: Files Cheap, permanent, simple storage Low level (Write, Read) Ap
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