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!
This constraint shows that the key attribute value in each tuple must be unique, i.e., no two tuples have the similar value for the key attribute. This is because the value of the primary key is used to recognize the tuples in the relation.
Example: If A is the key attribute in the following relation R than A1, A2 and A3 must be unique.
A
B
A1
B1
A3
B2
A2
Example: In relation PERSON, PERSON_ID is primary key so PERSON_ID cannot be given as the similar for two persons.
Integrity Constraint
There are two kinds of integrity constraints:
Where does view definition stored? A view definition is permanently stored as part of the database.
What is the archtetype/instance pattern? The archetype/instance pattern happens when one entity tracks occurrences of another entity. A common example is the relationship among
domain
design a generalization specialization hierarchy for a motor vehicle sales company. the company sells motorcycles, passenger cars, vens and buses.
Which element in the database can modified by changing the data dictionary? Data elements in the database can be changed or modified through changing the data dictionary.
How external/conceptual mapping and conceptual /internal mapping is performed
What is substitutability? Any method of a class-say A can equally well be adjured with any object belonging to any subclasses B of A. This characteristic leads to code reuse, a
What is difference among mysql_connect and mysql_pconnect? Mysql_connect() opens a new connection to the database while mysql_pconnect() opens persistent connection to the data
Determine the language that needs a user to specify the data to be retrieved with no specifying exactly how to get it is Ans: Non-Procedural DML
am looking for assignment helper for dbms
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