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!
One-to-one relationship:
For every 1:1 relationship type R in the ER diagram including two entities E1 and E2 we take one of entities (say E1) preferably with total participation and add primary key attribute of one more entity E2 as a foreign key attribute in the table of entity (E1). We will also have all the simple attributes of relationship type R in E1 if any.
For instance, the DEPARTMENT relationship has been extended to contain head-Id and attribute of the relationship. Please note we will maintain information in this table of only present head and Date from which s/he is the head.
There is one Head_of 1:1 relationship among FACULTY and DEPARTMENT. We select DEPARTMENT entity having total participation and add primary key attribute ID of FACULTY entity as a foreign key in DEPARTMENT entity named as Head_ID. Now the DEPARTMENT table will be as follows:
DEPARTMENT
D_NO
D_NAME
Head_ID
Date-from
A relation has: Relational Schema Relation instance Relational Schema: A relational schema shows the relation's name, its attributes and the domain of every a
I need to Map an E-R diagram to a relational schema
Define Deadlock recovery measures To recover from deadlock, the cycle in the wait-for-graph should be broken. The common technique of doing this is to rollbac
Describe the iterative and incremental life cycle For an iterative and incremental life cycle, two criteria are process and time. The main components of showing a project devel
What are aggregate functions? And list the aggregate functions supported by SQL? Aggregate functions are functions that take a collection of values as input and return a one va
With the linear commit protocol, sites are connected in a chain, and the subtransaction at the left-hand end of the chain initiates the protocol. Propose a crash recovery protocol
Depending upon the rules we have found, we can classify the locks into two types. Shared Lock: A transaction might be acquiring shared lock on a data item in order to read it
What do you understand by a view? What does WITH CHECK OPTION clause for a view do? - A view is a virtual table which comprises fields from one or more real tables. - It is
How to design a formal and exact model How to design a formal and exact model of real-world problems by applying findings of analysis phase of OMT. The object design phase find
Define what Immediate database modification technique uses? Ans: Both undo and redo.
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