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 algorithm of ER To Relational Mapping ?
ER-to-Relational Mapping Algorithm:
1) Step 1: Mapping of regular entity types: For each strong entity type E, form a relation T which involves all the easy attributes of a composite attribute.
2) Step2: Mapping of weak entity types: For each weak entity type W along with owner entity type E, create relation R and involve all easy attributes (or simple components of composite attributes) of W as attributed of R. In addition, involves as foreign key attributes of R, the primary key attribute (s) of relation(s) which correspond to the owner(s) and the partial key of the weak entity type W, if any.
3) Mapping of relationship types: form a relation R, for relationship along with primary keys of participating relations A and B as foreign keys in R. Further to this, any attributes of relationship become an attribute of R also.
4) Mapping of multivalued attributes: For every multilvalued attribute A, form a new relation R. This relation R will involve an attribute corresponding to A, plus primary key attribute K-as a foreign key in R-of the relation which represents the entity category or relationship type that has A as an attribute.
wh
Problem : AirwaysCentre, an international airline booking company currently uses a relational database system for their operations, which includes the following relations: P
10A.53 Code an Oracle Database trigger to enforce the constraint that an employee can never change his or her department. 10A.54 Code an Oracle Database trigger to allow the
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
assume we have the following apllicationthat model sccer team the games they play and the players inv each teamin the design we want to capture
Determine the concept of Process Process: A process transforms the data values. It is represented as ellipse containing a description of transformation. Each procedure has a
Define access time. Access time is the time from when a read or write request is issued to when data transfer starts.
Explain data abstraction? Data abstraction Data abstraction is a methodology in which enables us to isolate how a compound data object is utilized from the details of how it is
What are the key features of Oracle? Key features of Oracle are as follows: • Read Consistency • Concurrency • Locking Mechanisms • Quiesce Database • RAC • Portability
A file of employee have 10,000 blocks on a cylinder of a disk with characteristics r=8ms and btt=0.6ms I want to know the cost of read inthe file under following conditions for a q
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