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!
A relation instance indicates as r is a collection of tuples for a given relational schema at a exact point of time.
A relation state r of the relation schema R (A1,A2,..........AN), also denoted by r(R) is a set of n-tuples
r = {t1,t2,............tm}
Where each n-tuple is an ordered list of n values
t = 1,v2,........, vn>
where every vi belongs to domain (Ai) or includes null values.
The relation schema is also known as 'intension' and relation state is also known as 'Extension'.
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
Structure of Client Server Systems: In client/server architecture, clients show users who require services while servers give services. Both client and server are a combination of
What are the Issues when Selecting a Database Issues when Selecting a Database Storage space requirement: A database requires about triple storage space of the actua
3NF Normal Form A relation schema R is in 3NF if it is in 2NF and for each FD X A either of the following is true X is a Super-key of R. A is a prime attribute of R
Describe the Composite Key Composite Key: Sometimes one key is not enough to uniquely recognize a row. E.g. in a single class Roll is enough to search a student, but in the w
Limitations of File Based System The file-based system has some limitations. The limitations are listed as follows: Isolation and separation of data: When the data is
Define and differentiate between ordered indexing and hashing. Ans: Ordered indexing: To gain fast random access to records in a file, we can make of an index structure. Every
Design a gennalization and specialization hierarchy for an automobile sales company
Relationship between Security and Integrity: Database security usually refers to access, while database integrity refers to avoidance of accidental loss of consistency. But usually
Write short notes on domain relational calculus The domain relational calculus uses domain variables that take on values from an attribute domain rather than values for whole t
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