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!
Primary Key
The primary key is the candidate key that is selected by the database designer as the principal denotes of identifying entities within an entity set. The left candidate keys, if any, are called as alternate keys.
Foreign Keys
Let us first tell you the basic definition of foreign key.
Let R2 be a relation, then a foreign key in R2 is a subset of the set of attributes of R2, such that:
1. There be a relation R1 (R1 and R2 not essentially distinct) with a candidate key, and
2. For all time, every value of a foreign key in the present state or instance of R2 is identical to the value of Candidate Key in a few tuple in the present state of R1.
education.
Explain entity integrity and referential integrity rules within relational model. Show how these are realized in SQL? Entity Integrity Rule - No primary key value could be nu
write program
A database will be made to store information about patients in a hospital. On arrival, each patient’s personal details (name, address, and telephone number) are recorded where poss
FDs in Relationships: Enrols Relationship: None as it is many to many Teaches Relationship : Course code → Instructor Instructor → Course code The next question is:
what is completeness constrent?
Compare three clustering algorithms in Weka. For this comparison, you will need to use at least two different datasets. Run the algorithms on the datasets, and use the visual
How to create a biological database based on viruses. How to decide which attribute should be there in the table and schema? How to identify the primary keys, foreign keys, domain,
What is the use of a slotted-page structure and what is the information are there in the header? The slotted-page structure is used for organizing records within a one block.
Explain I command in QBE ? I : It is the command in QBE that is used to insert tuple (s) into the database
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: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd