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!
If R1 and R2 are two relations or functions, then the result of R3 = R1 × R2 is the combination of tuples that are in R1 and R2. The product is associative and commutative.
Degree (R3) =Degree of (R1) + Degree (R2).
In case, R3 will have tuples such that R3 = {t1 || t2 | R1 ∋ t1 ∧ R2 ∋ t2}.
Example:
R2
A
B
A1
B1
A2
B2
A3
B3
A4
B4
R1
C
C1
C2
R3 = R1 × R2 is
Relationship between Security and Integrity: Database security usually refers to access, while database integrity refers to avoidance of accidental loss of consistency. But usually
What are the properties of transaction? There are three properties of transactions :- A) Atomicity B) Consistency C) Isolation
UNION If R1 and R2 are two union compatible relations then R3 = R1 ∪ R2 is the relation having tuples that are either in R1 or in R2 or in both. In case, R3 will have tuples
What is inheritance? Inheritance is an object orientation concept that allows reusability of code / design. Basic sense of inheritance is that if one class is predefined than a
What is the need of a log in a DBMS? Briefly describe the various types of records that are normally present in a log. Ans: The system log, which is generally writt
Determine the minimal set of functional dependencies for the following data. This table is part of the OHSU database of extracurricular activities and tracks the DMICE band's co
Suppose that in an organisation, an employee may do different roles in dissimilar projects. Say, RAM is doing coding in one project and doing designing in another. Suppose that the
What is a Data Flow Diagram? Data Flow Diagram: A data flow diagram is the graph that shows flow of data values from their sources in objects in the course of processes whic
WHERE and HAVING clause in SQL ? The WHERE clause is commonly used for implementing conditions on each tuple of the relation. The HAVING clause is used in combination along wi
Describe file organisation? A file is organized logically as a sequence of records. These records are mapped onto disk blocks. A) Fixed-Length Records Type deposit=record
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