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!
Views in relational algebra:
1. Basic expression contains either
a) A relation in the database.
b) A constant relation.
2. General expressions are madde out of smaller sub expressions using
a) σp(E1) select (p a predicate)
b) ∏s(E1) project (s a list of attributes)
c) Px(E1)rename (x a relation name)
d) E1∪E2 union
e) E1- E2 set difference
f) E1x x E2 cartesian product
Benefits of Hashed file Organisation 1. Insertion or search on hash-key is quick. 2. Best if equality search is required on hash-key. Drawbacks of Hashed file
Explain group By clause in SQL? Group By clause in SQL: The GROUP BY clause can be used in a SELECT statement to collect data across multiple records and group the results thro
Explain the Deferred Update The deferred update methods do not physically update the database on disk till after a transaction reaches its commit point; after that the updates
Describe the host language? Host Language: You could write applications along with SQL statements embedded inside a host language. The SQL statements give the database inter
How many types of Views are there? There are Four types of views:- Database View Help View Projection View Maintenance View
Record based Logical Models: Use records as the key data representation components Examples: Relational Model: It shows data as well as relationship between data in the form
For problems 1-4, give all candidate keys for the tables with FDs specified. Composite candidate keys must be put in parentheses, and candidate keys must be separated with commas
Drawbacks of Database systems ?
what are the topics in data management
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
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