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.
Competition entrants can be either Individuals, or Teams. A Team is usually sponsored by a business, and, in that case, the team members would all wear T-shirts with the sponsoring
Horizontal Fragmentation- Horizontal fragmentation groups together the tuples in a relation that are collectively used by the main transactions. A horizontal fragment is produced b
What is Relational calculus? Relational calculus is a Non- Procedural language.
Eliminate Redundant Data In the "Database Relation" above, the primary key is made up of the D-ID and the Emp-ID. The database-name relies only on the D-ID. The similar databas
Explain the term- Query. Queries are used to repossess and show specific records in a table. They can also be used to show specific fields of specific records, which meet the co
Candidate Key: In a relation R, a candidate key for R is a subset of the set of attributes of R, which have the differnt two properties: (1) Uniqueness: N
what is stracture of dabms
explain normalisation
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
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
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