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 no primary key value can be null. This is as the primary key is used to recognize individual tuple in the relation. So we will not be able to recognize the records uniquely containing null values for the primary key attributes. This constraint is specified on single individual relation.
Example: Let R be the Table
A#
B
C
Null
B1
C1
A2
B2
C2
B3
C3
A4
B4
A5
C5
Note:
1) '#' shows the Primary key of a relation.
In the relation R above, the primary key has null values in the tuples t1 & t3. NULL value in primary key is not allowed, therefore, relation instance is an invalid instance.
Outer Join: The use of Outer Join is that it still joins those tuples that do not have matching values in common columns are also contained in the result table. Outer join places
A database for the Service and Maintenance (SM) section of a Computer sales and service Company has to be developed. SM gives after sales service to customers. SM branch has a numb
random file orgnization
Distributed query and transaction processing a. Construct a query around any one of the functional divisions you made in 4a such that if executed in the distributed design of 4
Write a short note on QBE? Stands for "Query By Example." QBE is a feature involved along with various database applications which gives user-friendly techniques of running da
Implementation and SQL Applications
Define Direct file organization? The direct file organization is employed to enhance the performance in accessing the records than sequential file organization. In direct file
#explain five disadvantages of a dbms..
What is Thread splitting A thread of control is a path by which a set of state diagrams on that a single object is active at a time. Objects are shared between threads
Ways for Selecting Data Structure Algorithms operate on data structure. Therefore, selection of the best algorithm means selecting the best data structure from whole bunch. Th
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